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THE 

WATCH ADJUSTER'S MANUAL 



A Practical Guide for the Watch and 

Chronometer Adjuster in Making, 

Springing, Timing and Adjusting 

for isochronism, positions 

and Temperatures 



BY 

CHARLES EDGAR FRITTS 

("EXCELSIOR") 

Author of Practical Hints on Watch Repairing ; Practical Treatise on the Balance 
Spring ; Electricity and Magnetism for Watchmakers ; How to Take 
In, Warrant and Deliver Work; etc., etc. 

Formerly Member of the British Horological Institute, IvOndon, England 



FIFTY-SIX ORIGINAL ILLUSTRATIONS 



third edition 

Revised and Corrected by the Author 



PUBLISHED BY 

THE KEYSTONE 

THE ORGAN OF THE JEWEI.RY AND OPTICAI, TRADES 

19TH AND Brown Sts., Philadelphia, U.S.A. 
1904 

\All Rights Reserved\ 



THE L?BflflRT~Sf' 

CONGR(-:s>5 
One Copy Rfeceivee 

OCT. 17 1904 

OWVWIQHT leNTnv 



L 



COPY A. 



X 



Entered according to Act of Congress, in the year 1894, 

By CHARI^ES EDGAR FRITTS, 

In the office of the I<ibrarian of Congress, at Washington, D. C. 



Registered at Stationers' Hall, I,ondon, England, 

By CHARIvES EDGAR FRITTS, 

in the year 1894. 



Entered according to Act of the Parliament of Canada. 

in the year 1894, 

By CHARI^ES EDGAR FRITTS, 

at the Department of Agriculture. 



Copyrighted in the year 1894, 

Under the Berne International Copyright Convention, 

By CHARI.es EDGAR FRITTS, 

In Belgium, British Empire, France, Germany, Italy, 
Spain and Switzerland. 



\^All Rights Reserved] 



y 



«\ 



x^l^ 



PREFACE TO THIRD EDITION. 



In issuing this Third Edition of The Watch Adjuster's 
Manual, it is opportune to state for the information and assur- 
ance of the reader, that since the work was first pubHshed only- 
two slight errors were brought to the notice of the author, and 
these were of such a trivial nature that they scarcely called for 
correction. This fact shows the extreme care and thoroughness 
with which the work was originally prepared, and is also proof 
of its accuracy and reliability of statement. It is also opportune 
here to make general acknowledgment of the letters received by 
the author from all parts of the world, giving assurance that the 
work was in truth what it was intended to be, the practical 
workman's standard authority. 

Unlike most technical treatises, the progress of time has 
added greatly to the value of this work. Railroad watch in- 
spection, which has now become almost universal, has made the 
very finest workmanship imperative, and such workmanship 
implies a thorough knowledge of the methods described in this 
book. And in this connection it may be added that the work- 
man who is qualified for railroad watch inspection has the best 
recommendation for the patronage of the community. 

The Publishers. 



CONTENTS. 



PART FIRST. 
PREPARATORY. 



PAGES 

Chapter I. — Suggestions to Workmen, . . . . i to 7 

Chapter II. — Preliminary Examination of the Movement, . 8 to 14 

Chapter III. — Magnetism and Magnetized Watches, . . 14 to 18 

Chapter IV. — The Demagnetization of Watches, Watch 

Parts, etc, 19 to 27 



PART SECOND. 
MAKING BALANCE SPRINGS. 

Chapter V. — Treatment of Steel for Making Hair Springs, . 28 to 35 

Chapter VI. — Making Cylindrical or Helical Springs, . . 35 to 41 

Chapter VII. — Making Flat Spiral and Breguet Springs, . 41 to 46 

Chapter VIII. — The Modern American Method of Making 

Hair Springs 46 to 49 



PART THIRD. 
WATCH BALANCES. 

Chapter IX. — Balance Making, 50 to 56 

Chapter X. — Selecting and Testing Watch Balances, . . 57 to 64 
Chapter XI. — Correcting and Finishing Balances, . . 64 to 69 



CONTENTS. 



of Vibra 



PART FOURTH. 
SPRINGING AND TIMING. 

Chapter XII. — Conveniences for Timing, 

Chapter XIII. — Means for Registering and Comparing 
Times, 

Chapter XIV. — Calculating the Proper Number 
tions, 

Chapter XV. — Counting the Vibrations, 

Chapter XVI. — Testing and Timing Hair Springs, 

Chapter XVII. — Hair Spring Fitting Tools, 

Chapter XVIII. — Fitting Hair Springs, 

Chapter XIX. — On Poising, .... 

Chapter XX. — Quick Ways of Bringing a Spring to Time, 

Chapter XXI. — Regulating Watches, . 

Chapter XXII. — Regulating Fine Watches, . 

Chapter XXIII. — Rating, .... 



pages 
70 to 73 

7S to 80 

81 to 84 

84 to 90 

90 to 96 

96 to 108 

log to 124 

124 to 131 

131 to 134 

134 to 145 

146 to 157 

158 to 167 



PART FIFTH. 
SPECIAL AND "NATURAL" COMPENSATIONS. 



Chapter XXIV. — The Four Principal Escapements, 

Chapter XXV. — Cylinder Escapement Watches, . 

Chapter XXVI. — Duplex Watches, 

Chapter XXVII. — Lever Watches, 

Chapter XXVIII. — Box and Pocket Chronometers, 



168 to 170 
171 to 179 
180 to iS3 
188 to 200 
200 to 212 



PART SIXTH. 
THE ADJUSTMENT FOR ISOCHRONISM. 

Chapter XXIX. — Isochronism, 21310221 

Chapter XXX. — Why Springs are Isochronous, . . . 221 to 231 

Chapter XXXI. — Methods of Securing Isochronism, . . 23210243 

Chapter XXXII.— Isochronizing by Terminal Curves, . 243 to 252 



CONTENTS. xi 

PAGES 

Chapter XXXIII. — Isochronizing the Cylindrical Spring, . 252 to 258 

Chapter XXXIV. — Isochronizing the Flat Spiral Spring, . 25S to 263 

Chapter XXXV. — Isochronizing the Breguet Spring, . . 263 to 271 

Chapter XXXVI. — The Isochronal Adjustment, . . . 271 to 287 



PART SEVENTH. 
THE ADJUSTMENT FOR POSITIONS. 

Chapter XXXVII.— Position Faults 288 to 298 

Chapter XXXVIII. — Adjusting for Positions, . . . 298 to 313 



PART EIGHTH. 

THE ADJUSTMENT FOR HEAT AND COLD. 

Chapter XXXIX. — Compensation, 314 to 320 

Chapter XL. — Apparatus for Adjusting the Compensation, . 320 to 327 
Chapter XLI. — Adjusting the Compensation, , . . 327 to 342 



TO THE READER. 



A note of the following corrections should be made on the 
margins of the pages referred to : 

TIME SIGNALS. — The methods of sending out noon time signals 
from the U. S. Naval Observatory, at Washington, D. C, as described on 
page 71, has been slightly changed. The signals now begin at 11. 55' a.m. 
instead of 11. 56''. 45'''' a.m., as before, and continue for five whole min- 
utes, giving sixteen opportunities for comparing time. During this 
period a signal is sent out for each second, except the following, which 
are omitted : the 29th second of each minute, the last 5 seconds of the 
first 4 minutes, and finally, the last 10 seconds of the last minute are 
omitted, followed by a signal at exactly 12 o'clock noon, standard time. 

The method of utilizing the signals is the same as before described. 

OVER-BANKING IN LEVER WATCHES.— It should be stated 
at the end of paragraph 469, page 196, that over-banking in lever watches 
is a fault of the safety action (469), and is due to the lever being too 
short, or some other fault, which lets the safety pin (or guard point) get 
past the roller in the wrong direction, or before the proper time, or 
before the safety pin gets in the crescent. It is most frequently caused 
by setting the hands backward. 

Whenever the instructions say that the safety pin or guard point is 
"too short," and the like, that of course means that the lever is too 
short, and that the safety pin or the guard point should be set forward, or 
towards the balance staff, and vice versa. See (469), lines 5 to 8, and 
especially line 14 to end of section. Also, see (465), lines 6 to 8 ; and 
(472), items No. 11, 14 and 15. The necessary instructions will all be 
found there somewhere, in their proper places. These corrections 
should always be made before beginning to work on the adjustments. 



THE 

WATCH ADJUSTER'S MANUAL. 



PART FIRST. 
PREPARATORY. 



CHAPTER I. 

Suggestions to Workmen. 

(i.) This book will be pre-eminently practical. Not that 
we would disparage theory — far from it. A knowledge of the 
theoretical principles of any art is the proper preparation for the 
most successful practice in it. But the majority of watchmak- 
ers would give more for an account of the actual practice 
among good workmen than for all the theoretical treatises ever 
published. This is not as it should be, but it is considered the 
part of wisdom to take things as they are. Hence the work has 
been made practical and exhaustive, going to the bottom of the 
subject, and useful to the most advanced workmen, as well as 
those with less experience. At the same time, enough of the 
theory of the different procedures is introduced, to enable the 
reader to understand the reason why he should do as described, 
as well as how to do it. 

(2.) Need of such a book. — The truth is that a very large share 
of our watchmakers are but imperfectly educated, either in 
theory or practice. The foreign system of long apprentice- 
ships is not in vogue here, and even if it were, the most of our 
employers are not really competent to instruct apprentices. 
Many of them are not workmen at all — only dealers in the 
goods of our line. Such as are good workmen are becoming 
more and more averse to taking apprentices because their time 



2 THE WATCH ADJUSTER'S MANUAL. 

is too valuable to allow of giving thorough instruction, as they 
could better afford to do under the old apprentice-laws, which 
on the whole were certainly better for both masters and men. 
The result is that half-fledged workmen abound — most of them 
conscious of their shortcomings and anxious to learn, but they 
are compelled to educate themselves, and to make their living 
while doing so. 

Again, many workmen have fully learned their trade, according 
to the old style, but everything has changed greatly since then, 
even within the last ten years, and they And that they are get- 
ting out of date. There are new kinds of work to be done, new 
tools and machinery to be used, new materials, new ways of 
working, and above all, greater excellence in every respect is 
required than would have sufficed in the old verge and lepine 
days. This change is constantly going on, even now, and the 
good workman of to-day will soon be left among the old fogies 
unless he keeps himself informed of all the current improve- 
ments. 

(3.) The way to become a good workman. — Let no one feel dis- 
couraged because he has never had proper instruction in the 
trade. If he really desires to be a good workman, and has 
true grit in him, there can scarcely be any training more severe 
and improving than patient study and practice, growing out of 
his own resources, and being held responsible for the perform- 
ance of his work, either by an employer or by a customer of 
his own. If he will persist in doing the best he can^ and improve 
every opportunity to learn, he will gradually regain the ground 
he should have made during his apprenticeship, and may in 
time become the equal of any, and the superior of those with 
greater opportunities but less determination to excel. A large 
share of our very best workmen are thus largely self-taught — 
thorough, independent, versatile and progressive, but the lack 
of a long and rigid apprenticeship has cost many of them a fear- 
ful loss of their time in the best years of their lives — a loss 
which it is the object of this book to lessen for its readers. 

Habits are all-powerful with a workman, and I feel the impor- 
tance of not leading any one into faulty or inferior ways of 
working. I shall try to tell all that is worth the telling, and 
worthy of being included in a first-class method of procedure — 
in fact, to give the latest and most advanced state of practical 
horology, so far as concerns the subjects treated herein. This 
involves the examination and comparison (either experimentally 
or judging from general experience) of perhaps scores of differ- 
ent tools, methods, etc., each claimed to be the best, in order 



THE WATCH ADJUSTER'S MANUAL. 3 

to sift out and arrange a complete, uniform and practically 
reliable system in each branch of work. 

(4.) Co7itents of the book. — While I shall not give all the new 
but visionary ideas floating about, I shall also exclude many 
old and generally accepted ones which I consider wrong in 
principle or superseded by better methods. I shall not only 
treat of things not generally known, but also of things very 
commonly done, but seldom done well, at least by learners, and 
which they need to know about, as they are at the root of all 
good work ; of some things that are highly important, and also 
of " little things. " But those little things are often just what 
constitute the difference between the good workman and the 
botch, which the former has learned by long and bitter experi- 
ence, the fruit of years of labor, study and trials. 

Much of what I shall say will, of course, be the standard 
practice among good workmen, and therefore not new to them. 
But I must take the risk of telling what is familiar to such, for 
the sake of that much larger class who have not had the oppor- 
tunities of the former for learning. Another large share, how- 
ever, will be the results of my own experience, investigations 
and observation, new and valuable even to experts and first- 
class workmen. I shall not claim perfection, either in judg- 
ment or experience, but simply lay the information before 
them and leave them free to accept or reject it as they think 
best. 

What we need in our trade is more life, study, interest; more 
discussions and even quarrels, if necessary, to wake us up; 
more rivalry in letting such light as we have shine for the benefit 
of all. And if I should use rather sharp language in regard to 
some persons and things in the course of these pages, as I 
propose to do, my sole object in stirring them up will not be 
any personal feeling or prejudice, but a desire to tell the exact 
facts, according to my knowledge and belief. 

(5.) Must put the directions in practice. — But let them mark 
this: — They can never really know a thing till they have ac- 
tually done it, and discovered by experience the peculiarities, 
dangers and difficulties of each operation. It matters not how 
carefully they read and understand, they must practice also. 
Instructions alone will not make one a workman, any more than 
a book of prescriptions makes a man a doctor. Therefore they 
should take the first opportunity, or make one, to put my direc- 
tions in practice. They will then learn many minor points 
•which space compels me to omit, will understand better what 
I do say, and they will remember it. Otherwise, as soon as 



4 THE WATCH ADJUSTER' S MANUAL. 

they lose sight of the book they will know scarcely more about 
it than they did before. So when a small tool or fixture is de- 
scribed let them go to work and make one. Each one will take 
but little time, which they will never miss, but they will soon 
have a goodly collection of them, at the mere cost of material, 
which they could not buy for any money, for the good reason 
that most of them are not on sale; and, having made them, they 
will know how to use them. The directions being in print, they 
can refer back to my very words and details a hundred times if 
necessary, and study and practice on them ad libitum^ till they 
are perfectly familiar with every point. The unusually copious 
Index will be a great assistance in quickly finding whatever is 
wanted. 

(6.) Annotating the book. — The workman who makes a spe- 
cialty of some particular class of work can somewhat simplify 
matters by carefully going over the book and marking in the 
margin of each page the parts which apply to his specialty. 
This will both familiarize him with the rules, and also aid him 
to instantly find any part to which he wishes to refer for further 
suggestions. Another way to annotate the book would be to 
mark every rule and section which is applicable only to some 
particular kind of watch. " M. Chr. " could be used to indicate 
marine chronometer: "P. Chr." for pocket chronometer; " D. 
L. ," for detached lever; etc. " H. Sp. " could mean helical 
spring;" " F. Sp.," for plain flat spiral; "Br. Sp.," for Breguet, 
and so on. Parts not so marked would be understood to have a 
general application to all kinds of watches or springs. The 
mere effort to analyze the meaning, and determine to what cases 
the rule applied, would make him more thoroughly acquainted 
with the subject than reading the book a dozen times over. 

(7.) Cross-references. — Another useful habit is to mark in the 
margin the number of any other section which bears on that 
point. This will greatly assist him in reading up on any partic- 
ular point, and collecting all the information relating to it. The 
sections are numbered, in order to facilitate this, and to avoid 
repetitions, so that any directions once given may afterwards 
be referred to for full details, and easily found. A great many 
such cross-references are already given in the text, but the in- 
tellectual peculiarities of each reader, and his way of reasoning, 
may make others beneficial to him. 

(8.) Make trie book a bench co7npanion. — The book gives the re- 
sults of the investigations, studies and experience of horolo- 
gists and practical men up to this time, and no better methods 
or rules are known to the trade. All available sources of in- 



THE WATCH ADJUSTER' S MANUAL. 5 

formation have been consulted, in order to make it complete, 
reliable and inclusive of the best theories and practices followed 
or known. 

The reader may reasonably depend upon it that, so long as 
the present styles of watches are used, the directions in this book 
cannot be superseded nor materially bettered, nor can experi- 
ence add very much that is new in the future, for they are the 
results of innumerable experiments, trials and inventions by the 
best watch and chronometer makers and adjusters everywhere. 
Moreover, it is the only special guide published, for practical 
watch and chronometer springers and adjusters. He should 
therefore make it his bench co7npanion^ keeping it always within 
reach, ready for constant reference, until he knows its contents 
perfectly. This habit of instantly looking up a point and set- 
tling it, makes the difference between a man who is constantly 
learning and improving, and one who is rapidly forgetting what 
he does know. 

(9.) Honesty thorough work indispensable. — Before closing, I 
wish to give a few words of advice which will have a very wide 
application, although addressed especially to young or inexperi- 
enced workmen. They should clearly understand that there is 
no royal road to success in our trade. No amount of experi- 
ence or knowledge, no costly instructions, or " trade secrets" — 
nothing whatever will suffice except good, honest, thorough 
work. Whatever other advantages they may have, that is the 
one indispensable thing. A watch is a machine; when it is all 
right, throughout, it will perform properly, and not before. 
Experience with thoroughness will make a fast workman, but 
never without. He should never knowingly slight any part, 
however small, for even after he has done his best, there will 
always be enough to apologize for. And, as my old master 
used to say, "you can't do it too well, if you try." This is 
what all old workmen will tell him, and he should settle down 
at once and forever upon that basis, and dismiss all ideas that 
there are any "secret ways," or ways that are not secret, 
known to any one, which will enable him to dispense with that 
requisite. Therefore it will be well for him to make up his 
mind never, under any circumstances, to shirk his work. He 
should do this for the sake of his reputation as a workman, of 
his self-respect as an honest man, and of avoiding the habit of 
shirking, which will surely grow upon him if indulged, till he 
will become actually incapacitated for doing a thorough job, by 
indifference and indisposition to exert himself. 

(10.) Don't do too much. — On the other hand, don't do too 



6 THE WATCH ADJUSTER'S MANUAL. 

much. This is a great fault with the inexperienced. They 
file, and bend, and hammer, and cut off, and make the most 
radical changes, on the slightest grounds or none at all. Now, 
a workman has no business to change any part of a watch un- 
less he knows the precise purpose of that part, and of its pecul- 
iar construction; knows that it ought to be changed, and why; 
knows what object it is desirable to accomplish by changing it; 
knows that the proposed change w411 accomplish that object, 
and how to make that change in a workmanlike manner. If he 
does not know the difficulty and its cause, and the proper 
remedy, he has no right to butcher a watch on the " cut and 
try" principle. When he cannot improve it he should at least 
not injure it, but rely more on head-work and less on guess- 
work. That, after all, is the real secret of excellence. Of 
two men, alike in every other respect, the best thinker is inva- 
riably the best workman. 

(i I.) The right way and the wro?ig ivay. — It will be noticed that 
the custom in some cases is to make the watch imperfect or 
wrong, /.<?., different from what would be strictly proper or 
right, in order to correct some error in the timing or to secure 
some special action. As examples I will mention the setting 
of the hair spring excentrically, putting the balance out of poise, 
opening the regulator pins widely, etc. If you should change 
such an arrangement in "putting the watch in order," you 
would ruin the adjustment, and make the watch worse off, in- 
stead of better. On the other hand, such imperfection may 
not be intentional, and then it probably ought to be corrected. 
It is necessary, therefore, to use good judgment in making re- 
pairs, so as to do whatever is really necessary and proper /// that 
particular case, and no more. 

(i2.) The right way. — Perhaps the only way to determine 
that point is to inquire, when the watch is left, what kind of 
time it has kept, and by whom it has previously been kept in 
order. If it has been in skilful hands and has performed well, 
it may safely be left as it is, unless the directions are to " put it 
in perfect order," in which case you should do your best to 
carry out the instructions. Even then, you will often be com- 
pelled to choose between long and expensive changes and some 
quicker makeshift which, while theoretically wrong, is practi- 
cally about as good as you would get it by the other way. In 
such cases, the decision will be largely determined by the value 
of the watch — and the temper of its owner. If it is an ordinary 
one, you would hardly be justified in making a bill of repairs 
almost equal to the value of the watch; but if it is a fine and 



THE WATCH ADJUSTER'S MANUAL. 7 

valuable article and the owner is willing to pay for having it 
put in perfect order, do that. It may seem rather out of place 
to advise the doing of imperfect work, but if that kind is what 
we are expected to do, and it will satisfy the customer, it may 
be considered excusable. 

(13.) Be careful what you do. — Especially when you get hold 
of a fine watch, be very careful what you do. Even when you 
see something which, according to the rules, is wrong, it may 
have been intentionally left so, or put so, as before stated. It 
may be a part of a laborious co-ordination of the various ac- 
tions in order to secure a good rate. If you change any part 
of it, you at once destroy the whole arrangement. The watch 
may not keep very close time and you may think that a certain 
alteration will improve it. You try it, and find the rate worse 
than before. You try this, that, and the other way, and finally 
you find that the way it was at first gives the best results — not 
so close as it ought to be, but the best that that watch is capable 
of doing without a radical overhauling and reconstruction. Al- 
most every one has had some such experience. Hence the advice 
to be careful what you do when handling a fine watch, or even an 
ordinary one which has been performing reasonably well. In 
addition to the suggestion in section (12), a good rule in all 
such cases is to notice how everything is, before taking it 
apart — making memoranda of every point, to prevent mistakes 
or forgetfulness — so that when putting it together again you 
can get everything precisely as it was before. 

(14.) Apparent contradictions. — Should there be any seeming 
inconsistencies in different parts of the book, it will be due to 
the effort to give a complete and candid statement of all the dif- 
ferent opinions and methods. The reader will perceive that 
some contradictions of the kind are unavoidable, after compar- 
ing the various opposing opinions on the subject of isochron- 
ism (536 to 541), and reflecting that opinions on other subjects 
are nearly as contradictory. I have endeavored to reconcile 
the old and the new as well as I could, and to be strictly fair 
and impartial in the statement of every case, but the reader can 
have no difficulty in knowing what my opinion is, if he wants 
it — and at the same time he is in a position to use his own judg- 
ment in the matter and to follow his o^vn opinion if he thinks it 
better. The book is not a set of rigid rules which must be 
obeyed, but it gives him full information of the opinions and 
methods of the best men in the trade, so that he is educated and 
posted up to date, and can intelligently make such use of his 
knowledge as he likes. 



8 THE WATCH ADJUSTER'S MANUAL, 

CHAPTER II. 

Preliminary Examination of the Movement. 

(15.) Prerequisites. It is not sufficient for the workman to per- 
form his special work properly. There are numerous extraneous 
points about the movement which, if not correct, will either 
prevent his job from giving satisfaction, or will so influence its 
performance as to give the appearance of faults which do not 
exist, and will perhaps render it difficult or impossible for him 
to secure a good adjustment or rate. I will therefore specify 
some of the points which should be looked after, and they will 
serve to suggest others which he may find incorrect. It is else- 
where stated how the hair spring should be pinned in the collet 
and stud, and various other matters relating to the spring, and 
I will proceed to mention other points seldom attended to as 
carefully as they should be. 

(16.) The Regulator. — As a general rule, the regulator-pins 
should be as close together as possible and yet leave the spring 
free between them. But if they are found otherwise, they 
should not be closed without good reason, for they may have 
been so opened for a purpose, by some one who fully under- 
stood the effects of so doing. But wide pins may justly be re- 
garded with suspicion. The effect of having the pins very 
open is not only to render the spring less susceptible to control 
by the regulator, but also to cause sudden and violent checks 
to its motion, making uniform progression of force (352) diffi- 
cult, if not impossible. Moreover, the spring vibrates upon the 
pin against which it rests, as a pivot or fulcrum, and the part 
beyond the regulator vibrates in a direction contrary to that of 
the normally acting portion, rendering it uncertain or difficult to 
regulate. The regulator is intended to act as the real stud, at 
the end of the acting part, and the pins should properly be as 
close together as they can be without binding on the spring 
when moved. The regulator should stand pretty well back 
towards the "slow" when the watch is regulated. The pins 
should both be tight in their places, so that they cannot yield 
any when the spring presses against them. If one of them has 
a foot, to close the bottom of the opening between them, the 
spring should be entirely free from it, nor should any dirt be 
allowed to accumulate there and touch the spring. 

See that the outer coil stands perfectly free between the regu- 
lator pins as they are moved through the whole of their sweep 



THE WATCH ADJUSTER'S MANUAL. 9 

from "slow" to "fast," not moving nearer to or against either 
pin at any point in the sweep. When you have occasion to 
take a watch apart for cleaning or any other purpose, which 
does not involve a change in the rate, it should be put together 
in such a way that the regulator should be at the same place, 
and the hair spring should occupy the same position between 
the regulator pins, as before it was taken down. To insure 
this, a careful examination should have been made, with the 
balance at rest, free from the motive force of the mainspring, 
and the position of both the regulator and hair spring noted 
down — for in a fine watch both of them have probably been 
carefully adjusted, and changing either of them or opening or 
closing the regulator pins might seriously damage the adjust- 
ment. Even in cheap watches, following this rule will fre- 
quently save several days in bringing them to time. 

But if a watch does not perform satisfactorily on trial, or if 
the workman is sure from inspection that it will not do so, 
the defective conditions must of course be changed and cor- 
rected. 

(17.) The end-stones^ if not held in settings, should be fast- 
ened there by cement. A loose end-stone is an abomination. 
When it is uppermost, it rests on the end of the pivot, and 
often can be seen wobbling about with every vibration of the 
balance. When the movement is inverted, the pivot rests upon 
the cap jewel and presses it down, but its position is very un- 
certain. It may possibly be level, but is much more likely to 
be otherwise, and may even tip up sideways so as to give little 
or no support to the pivot. Always fasten the end-stone in its 
cap or setting, either by a bezel or with cement. 

(18.) To cement the end-stone level, a good way is to put some 
shellac in the cavity, soften it by heat, place the end-stone in 
position, and while the cement is soft invert the cap upon the 
paper over the board, press the cap firmly down, and hold till 
cool. Pressing the cap down forces the jewel into the soft wax 
up to its proper place where it has the support of the metal, and 
insures that its surface will be level with the cap. If not so, it 
must be heated again till it becomes so. Generally, a cap or 
foot jewel should be just even with the surface of its setting or 
cap, not lower, nor sticking out any above it. But cases occa- 
sionally occur requiring a variation from this rule. Before al- 
tering or cementing a cap jewel, feel of it with a sharp-pointed 
piece to see if it is tight in its place. Also notice if it is pushed 
as far towards the hole jewel as it can be. The cap jewel 
should not quite touch the hole jewel unless the latter has been 



lO THE WATCH ADJUSTER' S MANUAL. 

cupped on the back side (726). If necessary, fit in a larger 
jewel, so as to bring its flat surface, when cemented, as it was 
before, if that was correct. 

(19.) How cemented. — A cap or foot jewel must invariably be 
fixed parallel with the under surface of the cap, or the upper 
surface of the slip, so as to present a perfectly horizontal sup- 
port for the end of the pivot. Otherwise it will slide down the 
inclined surface of the jewel and be wedged in against one side 
of the jewel-hole. This point must be carefully attended to. In 
the case of the foot jewel, which is out of sight, a little wax left 
outside of the jewel does no harm, and considerably strengthens 
the jewel. But for cap jewels, where no wax must appear to the 
eye, after prying the cap off the paper, and scraping the super- 
fluous shellac from the under surface, see that the jewel is flat and 
true, lay it down on the bench, the jewel underneath, and care- 
fully scrape the wax from the outside of the socket, without 
loosening the jewel. It will do no harm to leave a very little 
around the edge, as by again melting carefully, (and pressing 
down on the bench as before,) it will take a smooth, shining 
surface, and not be noticed. There are many workmen who 
denounce "sticking jewels in" with shellac as botchwork. So 
far as hole jewels are concerned I agree with them, but with 
cap and foot jewels it is often a necessity, and it is certainly far 
better than to plug the holes around the jewels with paper, sliv- 
ers of wood, etc., as we see every day. Doubtless our carping 
friends would sooner leave them loose than " stick them in" with 
wax. But then, some people are so ve?'y nice! 

(20.) The hands and their operating mechanism. — If the minute- 
hand, cannon pinion, or center post is suspected to touch the 
glass, place the thumb nail on the glass and run it along just 
over the hand, and by getting the light right, and looking 
through the edge of the glass, you can see the exact distance 
between its under surface and the hand. Or, put a small slip 
of paper over the post or hand, shut the glass on, hold the 
movement edgewise and tap on the glass. If free, the paper 
will drop off. Or, turn the hands and listen for any grating or 
squeak. Also look for any mark on the glass over the cannon 
pinion. If there be the slightest evidence of touching, a higher 
glass should be substituted. If that cannot be done, confine 
the end play of the center pinion or post, or, if that is correct, 
the top must be taken off a little. Be sure to turn the minute- 
hand once around, examining it frequently to see that it no- 
where touches either glass or dial, and does not "cant up" on 
one side and down on the other. If it does, the center pinion 



THE WATCH ADJUSTER'S MANUAL. ii 

wants uprighting. Also try if the hour-hand is perfectly free 
at every point during this revolution of the minute-hand. If not, 
it must be made so, for any binding will affect the time if it 
does not stop the watch, A black mark in the hole in the dial 
shows that either the hour wheel or the socket of the hand rubs 
there. If the hour-hand trembles or bobs or jumps as it is 
turned, it shows something wrong about the fitting of the dial 
wheels. If the seconds-hand points higher on one side than on 
the other, bring the hour-hand over it at its highest position to 
see if there is any possibility of their interfering. Also try if 
tne point of the minute-hand can touch it anywhere. 

(21.) Putting together. — In putting together a movement, 
the dial should first be fastened firmly to the plate so that it 
cannot move about or become loose, then the seconds-hand 
should be put on and trained as closely as possible to the dial 
without touching at any point of its revolution. The hour- 
hand is next put on firmly, turned to point exactly to the I, and 
the minute-hand put on pointing to the dot of the XII. This 
position will cause the hour-hand to point correctly to all the other 
figures, if the dial is correctly marked. In fitting it upon the 
hour wheel, the hour-hand when at its lowest end-shake must 
clear the seconds-hand at its highest, and the minute-hand, in 
turn, must clear the hour-hand at its highest, and, finally, the 
glass must clear the minute-hand at its highest point. Try this^ 
by pushing the upper hand down to its lowest possible end- 
shake, and, while so, lift the lower hand to its highest end-shake, 
one being just over the other. 

(22.) Freedo?n of the hands. — Hence the play of the different 
hands should be no greater than will give perfect freedom of 
motion. If the hour-hand has too much play, a spring foil 
washer should be placed on the hour wheel to prevent end- 
shake, but it must still remain perfectly free to revolve. The 
washer is not designed to exert any pressure upon the wheel 
when in its correct position, but only to prevent it getting out 
of its proper place and having unnecessary play. These 
washers are sold by all material dealers, and are so cheap that 
there is no excuse for the use of unyielding paper plugs be- 
tween the hour wheel and dial. Further details concerning the 
dial and the seconds-hand will be found in Chapter XXIII. 
(See Dial^ in Index.) 

(23.) Trying the hands. — Finally, bring the minute- over the 
hour-hand at the most dangerous place, hold the movement 
dial downwards, and with the key turn the minute-hand back 
and forth past the other while in that position, watching closely 



12 THE WATCH ADJUSTER'S MANUAL. 

when they pass each other. Too much care cannot be given 
to the perfect fitting of the hands and the mechanism propel- 
ling them, for any trouble here may prevent the most perfect 
movement from doing even decent service, and it is useless to 
undertake the regulation until it is corrected. If the glass is 
thin and it is suspected that it may be sprung down upon the 
center post and interfere with running, put a little rouge and 
oil on the tip of the post, shut down the glass and press it cau- 
tiously with the fingers, after pushing the post to its highest 
end-shake. If any contact occurs, the rouge will be found on 
the glass. Or the oily rouge can be left on the post while the 
watch is worn in the pocket for a few days, and the glass then 
examined. When satisfied that there is no contact, absorb the 
oil off the post with tissue paper. 

(24.) Ca7i7i07i pinion and center square. — If the cannon pinion 
or center post is loose, it may be tightened by twisting the 
arbor or post around between the jaws of a pair of dull cutting 
pliers. The sharp edges raise a couple of ridges or rings 
around the arbor, making it practically so much larger. If too 
large, twist the arbor in the flat pliers, which will flatten the 
ridges a little, till they just fit the cannon or center pinion 
snugly enough to surely carry the hands, but no tighter than 
that. By holding the arbor or post straight across the jaws of 
the cutting pliers and using reasonable care, there is not the 
least danger of either cutting or breaking the post off, or even 
bending it in the slightest degree. If this operation will not 
enlarge it enough, it is better to fit a new one than to tighten 
it with bristles or to flatten it with a hammer as many workmen 
do, for the former lasts but a little while, and both are sure to 
make the post and hand one-sided and probably cause " cant- 
ing, " besides lengthening it and disarranging the dial wheel 
mechanism. When the post is soft and but little enlarging is 
needed, it is often done by rolling it between two sharp files 
with a heavy pressure, thus producing a multitude of fine burrs 
on its surface. In a cheap watch, the cannon pinion is some- 
times filed in at one side, nearly to the bore, then a punch 
causes the thin metal to project into the bore enough to secure 
a tight fit. Just as I am finishing, a method is mentioned to 
me which, if practical, would be useful for tightening a cannon- 
pinion arbor or center square. I have not tried it. Make a 
solution by dissolving i part of cyanide of silver and 10 parts 
of cyanide of platinum in 100 parts of water. Immerse the 
worn part of the center post (or other worn piece) in this solu- 
tion and leave it there till the deposit upon it is sufficient to 



THE WATCH ADJUSTER' S MANUAL. 13 

make it tight in place. If too tight, the surplus metal can of 
course be filed off. Clean it well before putting in the bath, 
and wash thoroughly in water and alcohol after taking it out. 

(25.) A cannon pinion on a center post must be proof against 
any possible accidental turning. But if on a center-pinion 
arbor, it must only be tight enough to certainly carry the 
hands. If it has a tendency to work up and become loose by 
setting the hands, making a ridge near the top end of the arbor 
will generally cure this. But if the arbor is very much taper- 
ing, the part of it which forms the bearing in the cannon 
should be made more nearly cylindrical, or smaller at the base, 
then properly tightened. If the cannon pinion is tight enough 
in some places, but on turning it a little further around be- 
comes loose, this fault should be corrected by taking the 
*' humps" off the arbor, then ridging it at some place where it 
is round. In stem-winders, see that the stud holding the inter- 
mediate steel wheel is tight in place, also the stud of the minute 
wheel, and that both wheels operate properly, and cannot pass 
by, nor tip up and stick. Oil both studs, also the cannon 
pinion slightly^ to. prevent rust. See that the stem-setting 
mechanism cannot touch the dial wheels except when in action. 

(26.) Fuzee^ chain^ goifig barrel^ etc. — In fuzee watches, see that 
the end of the fuzee arbor cannot touch the case or dial, that 
the dust cup on the winding square does not rub where it goes 
through the dust cap; that the chain or its hooks do not 
rub — especially, if the mainspring has broken and bulged the 
barrel; examine when the bulged side is outermost, and the 
chain is on its highest part; if the teeth of the great wheel in 
a fuzee watch, or of a going barrel, are near the joints of the 
case, or where the ends of the case springs come when pressed 
in, be sure that they cannot touch. 

(27.) The balance., cock^ etc., in full-plate movement. — The screws 
in the balance should be tight, so that they cannot work out of 
themselves. See that the balance is free from the head of the 
barrel where it projects through the upper plate, and from the 
projecting point of the brace which supports the outer end of 
the mainspring. Both the brace and the barrel or its head may 
at times project upwards much higher than usual. Get the 
barrel up to its highest end shake, and see if the balance has 
ample clearance. See that an excess of oil does not exude to 
the top of the barrel, and hairs or dirt stick in it and clog the 
balance. See that the balance does not hit end of center-pinion 
pivot, steady pins, etc. 

(28.) Three-quarter plate movement. — See that the balance 



14 THE WATCH ADJUSTER'S MANUAL. 

screws are free from the chain on the barrel, (especially after a 
broken mainspring,) or on the fuzee; from the teeth of the go- 
ing barrel, and great wheel; from the center or fourth wheel 
pinion leaves; from the adjacent parts of the dust cap, or of the 
case, joints, springs, etc. If the balance has a banking pin, 
test its freedom by slowly moving the pin past the dangerous 
points. Do the same with the wings on the balance of a 
duplex. See if the wings are tight. See that the balance is 
free from the regulator where it passes over or under it. 

(29. ) Sundry faults. — See that the dust cap cannot be pressed 
down so as to touch the balance, (or its screws), nor press 
against the sides of the balance cock and displace it. See that 
the inner case canno*" touch the regulator center, or some 
screw or prominent point on the top of the balance cock, 
springing the latter down ind interfering with the freedom of 
the balance. If doubtful, or if the case is thin and liable to be 
pressed in sufficiently to touch, put a little rouge and oil on the 
highest or most probable points, and cautiously squeeze the 
case in, (listening at the same time, to see if it interferes with 
the vibration,) or wear it so for a few days. Look out for bent 
pivots on the balance staff, if the steady pins are tight and the 
balance cock comes off hard. See that the guard pin on the 
lever (in a full plate watch), cannot touch the regulator center. 
Turn the regulator in all positions, (with the balance out,) with 
the guard pin on each side, (/.<f., with the lever banked on each 
side,) to see that the guard pin cannot touch, and interfere 
with the locking, in English lever watches. 

The foregoing are of course not all the points which require 
looking after in a watch, but merely those which might affect 
the timing or rate, and perplex the workman if he did not know 
where the trouble was. 



CHAPTER III. 

Magnetism and Magnetized Watches. 

(30.) Effects of magnetism. — Besides the mechanical condition 
of the watch itself, we have to guard against an external dis- 
turbing influence which often produces vagaries in the regula- 
tion so incomprehensible as to cause the workman to give up in 
despair of overcoming them. This influence is magnetism or 
electricity, and is more commonly felt than is supposed by the 
majority of workmen. It has already been said that the balance 
should not be magnetized. Chronometer makers fully appreci- 



THE WATCH ADJUSTER'S MANUAL. 15 

ate the importance of this point, and try to guard against it by 
causing their balances to vibrate a turn and a quarter. By this 
means a balance is secured from the injurious effect, so far as 
it can be done. A magnetized balance has a constant tendency 
to turn to some particular position, like the needle of a com- 
pass, or to point to any other magnetized part near it, but 
with the above arc of vibration this tendency is partially neu- 
tralized, by the retarding and accelerating influences counter- 
balancing each other during the course of the vibration, so that 
less effect is produced upon the rate. If the magnetism is at all 
strong, however, the difference will not save the rate from be- 
ing ruined. Another advantage of vibrating i^ turns is that 
the effect of a want of poise is less than if the arcs are either 
greater or smaller. It is scarcely necessary to say that the ad- 
vantages thus secured are not confined to marine chronometers, 
but may be obtained in the same way for all watches, by giv- 
ing that vibration, when their balances are wholly or partly of 
steel, iron or nickel. Balances of palladium, gold or brass are 
not affected by magnetism, but steel screws used in their rims, 
or elsewhere in their construction, may have a disturbing influ- 
ence. In going-barrel watches, whose balances have varying 
arcs from the varying motive forces, if we make the average be- 
tween the largest and smallest vibrations to be \%. turns, we 
practically secure the advantages named as well as can be done 
in such cases. 

(31.) But the above precautions will not prevent evil effects 
from the application of a magnet near to a watch, and the 
effect is the same whether the case be open or shut. Powerful 
electro-magnetic batteries or machines will magnetize a watch 
at a distance of several feet, and persons who work around 
batteries, etc., should lay their watches aside during working 
hours. Even if the balance is of gold or brass, the magnet 
may attract the lever so strongly as seriously to disturb the rate. 
If the balance, balance spring, and lever with its pallets, are 
made of non-magnetic metal, it is of little or no consequence 
whether the rest of the watch is magnetized or not. But a 
magnetized lever or balance spring is very injurious, and a 
magnetized balance fatal to good time-keeping. Never allow 
any magnet or magnetized piece, loadstone, electric machine, 
galvanic battery, conducting wires, etc., near a fine watch, or 
carried in the pocket with it. Thousands of watches have been 
ruined by fooling around them with magnets, etc., either know- 
ingly or ignorantly, and when the watches are not injured by 
such a practice, their running is disturbed. It is often thought 



16 THE WATCH ADJUSTERS MANUAL. 

that a solid or uncut steel balance cannot be affected by mag- 
netism, because it is a circle. But the arms have ends, and 
may be magnetized or attracted the same as plain bars, not- 
withstanding that they are attached to a rim. The rim itself 
can be magnetized with two poles, or perhaps with several. 
A watchmaker should take no chance in such matters, but 
avoid even the possibility of his adjustments being interfered 
with by this or any other influences known to be injurious. If 
the owner insists on exposing his watch to injury, it is his priv- 
ilege to do so, — and to pay for it. 

(32.) Effect of dynamos^ electric motors^ etc. — At the present day 
magnetism is encountered almost everywhere. The electric 
motor is used on street railways, for elevators in buildings, for 
running machinery of all kinds and in all places, even for work- 
ing electric fans in offices, restaurants, residences, etc. Power- 
ful dynamos may be within a few feet of us in the building or 
under the sidewalks. Telegraph instruments, district messen- 
ger calls, telephones, and a multitude of other apparatus to be 
found in almost every house, contain magnets, which magnetize 
everything near them that is composed of iron or steel. A 
balance while vibrating is less affected than when still, and a 
hard balance or piece is less easily magnetized than a softer one, 
but the magnetism is more permanent and more difficult to re- 
move. Every time a watch is worn on an electric car, it is 
almost certain to be magnetized. 

{^tZ-^ Different ki7ids of magnets. — Tempered steel, when mag- 
netized, remains so, and is called a permanent magnet. Soft 
iron is a magnet while acted upon by another magnet or by an 
electric current, but loses its magnetism when the magnetizing 
influence is removed, and is therefore a temporary magnet. A 
coil of wire in which a current is flowing is a magnet, and one 
end of it is a North pole and the other a South pole, the same 
as a bar of steel or iron. When an iron or steel rod is placed 
in the coil, it becomes magnetized by it. Not only the coil, 
but the wire itself when straightened out, is magnetic while the 
current flows through it. A straight rod of magnetized iron or 
steel is called a bar magnet; when made in U shape, so that 
the poles or ends are near together, it is called a horseshoe mag- 
net. A coil of wire with an iron core in it is an electro-magnet. 

(34.) Action of magnetis?n. — A magnet of any kind acts by 
means of what are called magnetic lines of force ^ which spread 
out through the space near it. In the case of a powerful mag- 
net, these lines of force can be detected at least a hundred feet 
distant, and could probably be detected many times that dis- 



THE WA TCH A DJ US TER ' S MA NUAL. 17 

tance if we had sufficiently sensitive means for testing. The 
lines of force are closed circles. They come out of the North 
end or pole of the magnet, curve around through the neighbor- 
ing space, and into the South end, completing the circle in the 
magnet itself. In the magnet there may be millions of these 
lines, but outside they diverge in every direction and fill the 
entire space around, being most numerous near the poles, and 
less so as the distance increases. The magnetism is said to be 
powerful or weak, according to the number of lines of force 
passing through the object being tested. 

Magnetic attraction is due to the attraction of these lines for 
other lines of opposite direction. They tend to unite and con- 
tract or shorten themselves up. Magnetic repulsion is due to 
the repulsion between lines of force having the same direction — 
whether the lines belong to the same magnet or to different ones. 

(35.) All substances permeable by magnetis7?i. — M agnetism passes 
freely though all substances, whether animate or inanimate. 
It will pass through a brick or stone wall, a wooden partition, 
a human body, living or dead, precisely as if they were not 
there. Nothing can stop it. Air, water, glass, paper, cloth, 
metals, and everything else are permeable by magnetism. A 
magnet will therefore act on a balance in the case as well as if 
outside. The only difference is that when it acts upon a com- 
plete watch, its strength is distributed among all the steel or 
iron parts it contains, while the whole strength could be 
directed upon the balance by taking that by itself. Hence you 
must take the watch apart if your magnet is weak; but if it is 
strong enough you can magnetize or demagnetize the whole 
watch at once with it. 

i^Z^.^ Magnetic metals. — Although all substances are permea- 
ble by magnetism, only the magnetic metals can be magne- 
tized. They are iron, both wrought and cast, and steel in all 
forms; nickel is slightly magnetic, chromium and manganese 
much less so. But for all ordinary purposes, we may call 
iron and steel the magnetic metals. While the magnetic lines 
of force are passing through them, they are magnets. Magnets 
attract the magnetic metals and the latter attract magnets, the 
attraction being mutual. But two magnets attract each other 
more strongly than one magnet and an unmagnetized piece. 
A magnetized balance attracts every other magnet and piece of 
magnetic metal in the neighborhood, whether in the watch or 
out of it, and is attracted by them. Hence it is useless to de- 
magnetize a balance, and leave other parts magnetized such as 
pinions, case springs, etc. The attraction between them is 
2 



i8 THE WATCH ADJUSTER' S MANUAL. 

diminished, but it is still acting upon the balance and they will 
gradually remagnetize it. The only proper course is to demag- 
netize every piece of steel or iron in the movement and case, 
and to keep magnetized articles away from it. A magnetized 
pocket-knife, steel chain, button hook, suspender buckles, spec- 
tacles, buttons, truss or other springs, and similar articles on 
the person, will affect the motion of the balance. In the same 
way, magnetized iron beams or parts in the building, magne- 
tized tools on the bench, and the like, will affect the running 
while in the shop. 

(37.) Testing for magnetism. — Take a piece of perfectly soft 
iron (not steel) binding wire, about one-half inch long, and say 
No. 20 to 24, tie a fine silk fibre around the middle of it, and 
fix the other end of the fibre in a slit in a stick of pegwood. 
This " tester" will swing freely, and will point in any direction 
indifferently, so long as it is not influenced by a magnet. But 
if there is a magnet in the vicinity acting upon it, the tester 
will /^/>// towards the magnet. Turn it away, and if it swings 
back and points in the same direction as before, move it in the 
direction it points, and you will find where the magnet is. If it 
ceases to point, when you move it so, you are going the wrong 
way, and should move in the opposite direction; when you get 
it close to the magnet, it will be drawn bodily towards it, and, 
if allowed to touch, will stick to it. To test a watch, hold it 
around the rim of the case, or open the case and hold it over 
the suspected piece. Remember that magnetism acts through 
the case, glass, etc., as well as through air. If there is no mag- 
netism present, it will not be attracted nor "point;" if there is, 
it will point, and will be attracted to the magnetized piece. 
You can thus test a balance or a watch without taking it apart. 
It is well to make two of these, so that you can discover if 
either of them has become slightly magnetized, as in that case 
they will attract each other and stick together. They should 
then be heated red-hot to remove the magnetism, and again 
suspended, without bending, hardening or working at them in 
any way. When in proper order, they will not attract each 
other at all. 



THE WATCH ADJUSTER'S MANUAL. 19 

CHAPTER IV. 

The Demagnetization of Watches and Watch Parts. 

(38.) Demagnetization. — A piece which has been magnetized 
by a powerful magnet, requires correspondingly strong magnet- 
ism to demagnetize it, but the latter need not be quite so strong 
as the former. But if they are not equally distant from the 
piece, there may be a very great difference in their strengths, 
for the effects are, roughly speaking, inversely as the cubes of 
the distances. That is, if the magnet which magnetized the 
piece was 10 feet from it, while the magnet which is used for 
demagnetizing is i foot from it, and both are of the same 
strength, their influences upon it will be in the ratio of i to 
1,000. Consequently a magnet close to it could remove the 
magnetism produced by another magnet 1,000 times as strong 
— provided the latter was 10 times as far away. It is from this 
reason that ordinary magnets can undo the effects of powerful 
dynamos, etc. But if a watch is held close to the dynamo or 
magnet, or in contact with its poles, as is sometimes foolishly 
done, a demagnetizer of nearly equal strength will be required 
to thoroughly remove the magnetism. 

(39.) The principles of demagnetization. — Demagnetization is 
accomplished by causing the lines of force to pass through the 
magnetized piece in the wrong direction. Supposing the piece 
to be a balance whose center bar has North polarity at one end 
and South polarity at the other, its lines of force come out of 
the North end and re-enter at the South end, as before explained. 
If we take another magnet and present its North end to the 
North pole of the balance, its lines of force will force their way 
through the center bar in the unnatural direction, or will pre- 
vent the home lines of force from emerging from the center 
bar, if we may so express it. What really occurs is unknown, 
but the result is that the molecules of the steel become differ- 
ently rearranged, and the center bar is no longer magnetized. 
This is supposing that the opposing influences are nearly equal. 
But if the magnet is not strong enough, all of the magnetism 
will not be removed ; or if it is too strong, or is continued too 
long, it will not only remove the magnetism, but will remagne- 
tize the center bar in the opposite direction, i.e.., will cause in 
it lines of force in the same direction as its own. In actual 
practice with a bar magnet, many trials and corrections are gen-; 
erally required to entirely free the piece from magnetism. 



20 THE WATCH ADJUSTER'S MANUAL, 

(40.) Testing the polarity. — In order to tell what the condi- 
tion of the piece is, or what effect has been produced, we need a 
polarity indicator. To make one, we take about an inch of a 
small sewing-needle, break off the eye and the fine point, and 
magnetize it powerfully by rubbing one pole of a bar magnet 
over it several times from end to end. Call the point the North 
pole ; then we rub the South pole of the magnet from the eye to 
the point of the needle — always in the same direction, and 
holding the magnet far away while returning it to the eye. 
Next, we rub the North pole of the magnet from the middle to 
the eye several times, and finish by repeating the first rubbings, 
from the middle to the point. The polarity of a piece thus 
treated is opposite to that of the magnet at the last point of 
contact. Thus, if the South pole touches the needle last, at 
its point, the point will be a North pole. Suspend this in a 
bottle by a fine silk fibre attached to the middle of the 
cork. When it is not affected by the proximity of magnetic 
metal, this will point to the North like a compass needle. A 
delicately balanced pocket compass needle can be used, but is 
not so good for our purposes, unless we want to know how 
much it is deflected from a true Northern direction ; in that 
case, a compass having a card divided off in degrees would be 
necessary. 

(41.) Disti?igu\shi?ig magnetized fro7n fion-uiagnetized pieces. — 
This needle is attracted by every piece of magnetic metal, 
whether magnetized or not. If the piece is not magnetized, 
either end of it will attract either end of the needle; but if it is 
magnetized, its ej\d will attract one pole of the needle and repel 
the other, accorciing to the law of magnets, that icnlike poles 
attract each other but like poles repel. That is, if the fork end 
of the lever, for instance, attracts the North pole of the needle, 
the fork is of South polarity; if it repels the North end of the 
needle, it also is of North polarity, and the distance that it re- 
pels (or attracts) it, shows whether the magnetism is strong or 
weak. If we tested a piece, then treated it to remove the 
magnetism, and it again repelled (or attracted) the needle, but 
not so much as before, we have weakened the magnetism. But 
if it repelled the needle, and, after treatment, it attracted, we 
have reversed the magnetism. In testing a balance, we first try 
all parts of the rim, center bar, staff, etc., with the tester (37). 
If that shows the existence of magnetism, and we want to know 
its location and polarity, we approach the different parts to the 
point of the needle, and observe whether they attract or repel 
it, and how much, thus learning the exact condition of the 



THE WATCH ADJUSTER'S MANUAL. 21 

piece. If the magnetism is strong, we shall need a powerful 
magnet to remove it. 

(42.) Clark' s method of demagnetizing. — This method is used 
when the workman has only a small bar magnet to operate 
with. Each piece is treated separately. Supposing it to be a 
lever or similar piece, we will call the magnetized ends or poles 
N. and S. Lay the bar magnet on a paper box or wooden block 
to raise it an inch above the bench, with the N. pole towards 
you. Take the piece in brass or wooden pliers, (anything ex- 
cept steel or iron,) bring its N. end up as close to the N. pole of 
the magnet as possible without touching, then present the S. 
end to the magnet about ^ inch from it, then the N. end ^ 
inch away, and so present the ends alternately, and each time 
a little further away, till it is several inches from the pole of 
the magnet, when the magnetism will probably be out. This 
can be told by the tester and the needle. Do not test it with 
the needle unless the tester (37) shows that it is still magne- 
tized, for the needle will remagnetize it. The distances can be 
told by holding a divided rule up to it. The balance and hair 
spring could also be treated in this way, but the balance gener- 
rally has to be treated on different sides, and the hair spring 
should be removed from the staff and enclosed between two 
pieces of card or thick paper having a hole punched for the 
collet to come through and the edges folded over the spring. 
Hold the cards tightly together while presenting the spring. 
Case springs can be demagnetized by heating red-hot and re- 
tempering them, or as above. 

(43.) The Waldo tnethod. — Straight and similar pieces are 
treated with a bar magnet as described below. You can make 
your own bar magnets from pieces of bar steel, charged in the 
way described in section (40). They need frequent recharg- 
ing, as they rapidly lose their magnetism. A strong horse-shoe 
magnet can be used for charging, by using the proper pole each 
time. For treating a balance, the bar magnet should be about 
3 inches long and ^ inch square. Find where the magnetism 
is strongest, and its polarity, by hanging it on a brass wire 
and bringing the pole of the magnet near the end of the arm. 
If it is attracted towards the magnet, try the other pole and 
it will be repelled. Take the balance in the hand and touch 
the pole momentarily to that part of the rim, then test with the 
tester to see if the magnetism is removed. Continue this till 
that point is free from magnetism. Then treat the other end 
of the arm in the same way; also, all around the rim, till the 
magnetism is all out. As it becomes weaker, use a weaker 



22 THE WATCH ADJUSTER'S MANUAL. 

magnet, to avoid overdoing it and reversing the magnetism. 
Always use the like pole to repel or drive the magnetism out 
(39). It may require half an hour to demagnetize a balance by 
this method. 

(44.) The Mayer method. — Prof. Mayer demagnetizes the 
whole watch at once, by oscillating it before the pole of a 
strong bar magnet. His method is somewhat modified in the fol- 
lowing description, to make it simpler and shorter. Put a slip 
of paper under the balance, to keep all the parts still during 
treatment. The watch (in the case) is tested as a whole, by 
laying it on the bench near the needle, to find the strongest 
magnetic points and their polarity. Suppose that the side at 
III (on the dial) has the strongest South polarity, and at XI is 
the strongest North polarity. You arrange the magnet M at 
the edge of the bench, as shown in Fig. i, (or on a book or 




Fig. I. 

wooden block will do,) and hold the watch near it, with the 
strongest North point (at the figure XI) before the North pole 
of the magnet, i.e., so that they repel. The line X, X\ should 
pass through the center of the watch and also through the axis 
of the magnet. Taking it in both* hands, oscillate the watch, 
holding it alternately in the positions W and W^. After doing 
this several times, reverse the magnet, bring the strongest South 
point (figure III) opposite the South pole of the magnet and 
oscillate it as before. Then again find the strongest magnetic 
points in the watch, and treat them in the same way, repeating 
this until there is no perceptible magnetism anywhere. As the 
magnetism gets weaker, hold the watch further from the mag- 
net and oscillate it fewer times, to avoid reversing the magnet- 
ism. This should be done at a distance from any iron or steel 
objects, otherwise they would attract the magnetism and inter- 
fere with the operation. 

(45.) The Maxim method consists in subjecting the watch 
to rapid alternations of magnetism while slowly withdraw- 



THE WATCH ADJUSTER'S MANUAL. 23 

ing it from the magnet, and thereby constantly weakening the 
magnetism till it ceases to be appreciable. This is done by a 
special machine which is patented, and is rather costly — the 
price being at one time as high as $250. I will explain the 
method as elucidating the principles of demagnetization. A 
bar magnet, carried on a vertical axis, revolves around that 
axis in a horizontal plane. The watch is carried on another ver- 
tical axis and is held in a frame so that it revolves in a vertical 
plane, while the frame itself revolves in a horizontal plane. The 
watch is thus turned both horizontally and vertically at the 
same time before the magnet, which is turning horizontally, 
and is slowly drawn from it by a horizontal screw. 

(46.) Demagnetizhig with horse-shoe magnet. — It is hardly 
worth while to fit up special apparatus unless it will demagne- 
tize the whole watch at once. A powerful, permanent magnet 
should therefore be used, or two to four of them may be ar- 
ranged together in a magnetic battery. Clamp the magnet in 
a wood block which can be held in the lathe, so that there will 
be wood in the bend of the magnets and also between the mag- 
nets and the lathe chuck. The central line of the spindle runs 
through the center of the bend and midway between the legs 
of the magnet, which revolve around the central line of the 
spindle. If more than one magnet are used, they are clamped 
together, with all the North poles on one side and the South 
poles on the other. While the magnets are revolving, hold the 
watch flatwise before them as closely as is safe, and very 
slowly draw it back, say i inch in the first 15 seconds, the next 
inch in 10 seconds, and at that rate till it is a foot away. Then 
test it, and if any magnetism remains, hold the other side to the 
magnets and treat as before. If that does not cure it, take out 
the case spring or/ other piece that is so strongly magnetized, 
and treat it separately. 

(47.) Demagnetizing with alternati7ig current. — If you are on 
an electric light or power line which uses the alternating cur- 
rent, you can get the company's electrician to wind up a sole- 
noid, or coil without a core, so that an alternating current of 
high intensity can be sent through it. Hold the watch in this 
for a few seconds, then slowly draw it away as before de- 
scribed, while the current is still flowing, till it is two or three 
feet away, when the current may be be cut off. If you are 
where you can conveniently reach an alternating current 
dynamo, or powerful motor, it will be still cheaper to hold the 
watch near to one of the poles and gradually draw it away. 
But be careful not to touch any part and get the current 



24 



THE WATCH ADJUSTER'S MANUAL. 



through you, or you may be demagnetized yourself — and per- 
haps devitaUzed. 

(48.) Demagfietizing 7vith an electro-mag Jiet. — If you are on a 
continuous or direct current line, you can use the current to 
energize an electro-magnet, fastened to the lathe spindle, 
whose arms are parallel with the axis of your lathe, and oper- 
ate it as before directed for horse-shoe magnets (46). In this 
way you can make your magnet as powerful as you like, by 
using a strong current or large coil on the magnet, and can de- 
magnetize a watch thoroughly in a few minutes. It would re- 
quire too much space to describe the construction so that one 
not familiar w^th electricity could make such an apparatus, but 
any electrician can make you one at small cost. The only 
difficulty is in making the two contacts for conducting the cur- 
rent to the electro-magnet while revolving. The current is not 
reversed in the electro-magnet, and only plain contacts are re- 
quired. If not convenient to employ an electrician, you can fit 
up a different apparatus which will answer all purposes. It 
consists of a simple current reverser, made to screw into the 
lathe spindle as a chuck, and neither the magnet nor the 
watch revolves. The magnetism is reversed in the magnet, 
and the watch slowly drawn away, as described for the horse- 
shoe magnet (46,), and the effect is the same. 

(49.) Description of the de?nagnetizifig apparatus. — Fig. 2 is a 
top view of the reverser, also showing the electrical connections 




Fig. 2. 



between the battery or dynamo and the coils of the magnet. 
The reverser is a boxwood or hard rubber rod. A, A, covered 
with a brass tube B, B, cut into two parts as shown. The shape 
of the cut is the same on both front and back sides, and is filled 
flush with sealing-wax, to insulate the parts of the tubing from 
each other. D represents the battery or other source of 
current, and wires conducting the current to brushes i and 2. 
Fig. 3 is a side view of the chuck and brushes, which are brass 



THE WATCH ADJUSTER'S MANUAL. 



25 



springs bearing on the tubing, and faced with thin platinum or 
silver where they rub on it. Fig. 4 is an end view of the same, 
showing the brushes on a wooden or rubber block C. In Fig. 
2, brushes 3 and 4 connect to the electro-magnet J/", and ^ is 
the watch to be treated. In the position shown, the current 
flows through wires and brushes i, 4, magnet, 3, 2, and back 



-^ 




Fig. 3. 



^ 



o 



feci. 



Fig. 4, 



to the battery. When the reverser has revolved half a turn, 
the course will be i, 3, magnet, 4, 2, thus reversing the direc- 
tion of the current through the magnet twice in each revolution, 
and thereby reversing its magnetism. To stop the current, slip 
a piece of paper between the reverser and one of the brushes, 
then disconnect the wires wherever most convenient. Or you 
can use a switch to turn the current on and off. If a battery is 
used, arrange at least five to ten cells in series. Keep all the 
contacts clean and free from oil or grease. Always disconnect 
the current before the reverser stops revolving. 

(50,) Demagnetizing apparatus of different kinds are sold 
ready made, and will save the trouble of fitting up apparatus, 
if they are efficacious. To test a machine, magnetize an old 
balance or a hard case spring on the pole of a dynamo or 
strong motor, and see if the machine will demagnetize that per- 
fectly. If it is claimed to be able to demagnetize the entire 
watch at once, test it in that way. The directions already 
given will explain the principles of the process, and be useful 
even if you buy a complete apparatus, because you will under- 
stand the philosophy of its management and operation, and can 
work with greater certainty and rapidity. 

(51.) Care of inag?iets. — Permanent magnets should always 
be arranged in a closed magnetic circuit while not in actual use, 
(i.e., their poles connected by soft iron,) as that preserves their 
strength, or prevents them from growing weak so fast as they 
otherwise would do. Horse-shoe magnets are always provided 
with soft iron " keepers" for connecting the poles, and so clos- 




26 THE WATCH ADJUSTER' S MANUAL. 

ing the circuit with magnetic metal. The keepers must of 
course be removed while using the magnet. Bar magnets can 
be preserved in the same way, as shown in Fig. 5, where b b 

are two bar magnets and k k are 
soft iron pieces or keepers, to 
connect their ends. The poles 
of the magnets are as shown by 
N and S on each. When not in 
use, permanent magnets should 
Fig. 5. be kept in a sheet iron, covered 

box, which has been heated red- 
hot and very slowly cooled to soften it. The object of this is 
to prevent the magnetism from spreading beyond the box and 
magnetizing everything around. If the tester shows strong 
magnetism outside of the box, it is not thick enough, and a 
box should be made of heavier iron. All electro-magnets and 
magnetic apparatus near the watch bench or watch rack, which 
must remain there, should have a similar shield around them. 
But they should be removed elsewhere, if possible, and no mag- 
net of any kind, or magnetized piece, allowed there. The 
action of keepers and shield is due to the fact that soft iron 
offers many thousand times less resistance to the passage of 
magnetism than air and most other substances, and the lines 
of force will pass through the iron rather than the air. By 
arranging iron so that it will conduct the magnetism past any 
object, it acts as a shield for it. The box and the keepers act 
by conducting the magnetism from one pole to the other, with- 
out the necessity of going through air. This choice of paths is 
the reason that iron or steel " attracts" any magnetism in its 
vicinity. 

(52.) Care of tools ^ etc. — Demagnetize perfectly all tools and 
materials used around watches. The operation of demagnetiz- 
ing must not be done on the watch bench, but in the back shop, 
and as soon as the article is freed from magnetism remove it 
tjtstantly to the front shop, or it will again be contaminated. 
Take no tools from the bench to the back shop except for de- 
magnetization, and allow no tools from the back shop on the 
watch bench. Any watch that is magnetized should be kept 
away from others. 

(53.) Necessity of under sta7iding this subject. — Inasmuch as 
magnetism is well known to affect the rate of watches, and regu- 
larity is impossible when they are under its influence, every 
springer and adjuster should understand how to free them from 
magnetism, at least, while timing and adjusting, or else he can- 



THE WATCH ADJUSTER' S MANUAL. 27 

not depend upon the rates observed during his trials nor secure 
a correct adjustment. While the frequency of exposure to 
magnetizing influences is constantly and rapidly increasing, 
the methods of protection are not. In fact, it is by no means 
certain as yet whether we know of either a compensation bal- 
ance or a balance spring, not liable to be magnetized, which 
can fill the place of steel and be depended upon to perma- 
nently retain its good qualities. Palladium balances and 
springs are giving good results, and it is to be hoped that 
longer and more extensive use may demonstrate that their good 
qualities are permanent. 

But steel will, for a long time to come, at any rate — continue 
to be used in ninety-nine hundredths of the watches made, and 
the watchmaker must necessarily learn how to protect it, or to 
rescue it, from this insidious enemy. No workman who does 
not know this can do good work, nor avoid actually injuring 
the watches which pass through his hands. And what is worse, 
he cannot even restore those which come to him daily for de- 
magnetization. 






PART SECOND. 
MAKING BALANCE SPRINGS. 



CHAPTER V. 

Treatment of Steel for Making Hair Springs. 

(54.) Materials employed for hair springs. — The material gen- 
erally used is the very best quality of cast steel, specially pre- 
pared and drawn into wire. It has the objection of liability to 
rust, and to be affected by magnetism, but thus far no substi- 
tute has been found which is positively known to have all of its 
valuable qualities and be free from these defects. Alloys of 
gold and palladium have been used, and further information 
regarding them will be given in sections (98) and (100). I will 
first give the method of making springs of steel, the material 
almost exclusively used. 

(55.) JjHparting elasticity to steel. — Steel may be made elastic 
either by hardening and tempering, or by compression, and 
springs are made in both ways. Springs for marine chrono- 
meters are now almost always hardened and tempered, as are 
those for the finer classes of pocket watches — while cheap 
springs are wire-drawn and rolled to all degrees of hardness, 
then wound into shape, and blued by heat, which causes them 
to " set" in the proper form. The former are more expensive, 
but are in every way preferable when properly made. Their 
temper is more uniform, both in the body of the spring and 
throughout its length ; their qualities, whatever they may be, 
are more permanent, and they are more certainly made of any 
desired temper. Where the elasticity is given by drawing 
through wire plates and by rolling, there is the danger of minute 
cracks being produced in the edges at the final rollings, when 
the wire is already hard, which, although imperceptible to the 
sight, will disturb the action of the spring. But if the spring 
is to be hardened by fire, it can be annealed and kept in safe 
workable condition till the moment of hardening. 

(56.) Draiving the spring wire. — In drawing (or rolling) the 



THE WATCH ADJUSTER'S MANUAL. 29 

wire it is important, ist: To draw always from the same direc- 
tion, and, if it is rolled upon a spool after each drawing, it 
must be unwound and re-rolled before drawing again, so as to 
commence with the same end each time; 2d: To draw at a 
regular rate of speed — not fast at one time, then slow, etc., for 
such irregularity of speed will produce irregularity of texture 
in the wire; 3d: To have as few stops as possible, for there 
will be a difference of texture at that point of the wire that is in 
and behind the plate at the time of the stoppage, no matter 
how short the stop may be. The best way is to draw the whole 
length of the wire through at a regular speed without stopping 
at all ; 4th : Wind the wire upon large spools or bobbins, if at 
all, and do not cramp or bend it any more than is unavoidable, 
until it is made up into springs; 5th: Instead of oil use bees- 
wax as a lubricant; that will adhere to the wire under any pres- 
sure, while oil will not; 6th: Before heating the wire, either to 
harden or " set" it, clean it thoroughly by rubbing it lengthways 
with a rag dipped in pure (or ^2> per cent.) alcohol, and then do 
not handle it with the bare fingers, but with clean tools, or by 
interposing clean paper or cloth between the skin and the steel. 

(57.) Selecting the spring wire. — First cut off a piece and see 
if it will harden properly at a cherry-red heat. If not, it is un- 
suitable for springs, because it is too "mild,"/.^. , it contains 
too little carbon for good spring steel, and is more like iron. 
If, when quenched in cold water, it becomes glass-hard and 
brittle, it will answer. Then examine the spool, to see if the 
wire is rusty, twisted, marred or scratched, or full of bends or 
kinks. If so, reject it. It should be clean, with a bright, 
polished surface, of a uniform size and shape, and carefully 
coiled on the spool to avoid short bends. 

(58.) Annealijig the steel. — If you have occasion to anneal 
and soften the steel, (for drawing, or any other purpose,) 
wind it on an iron spool or bobbin, as closely and solidly 
as possible, (without getting any short bends in it,) heat it 
in a cyanide bath {6t,) which just begins to be visibly red in a 
darkened room, till the steel is well heated through, then 
quickly quench in water. Dry in alcohol, then heat again to 
a dull red heat in daylight, and lay it in hot ashes, covering it 
deeply in the hot mass and leave till perfectly cold — an entire 
day, if necessary. The quenching process, if the heat is just 
short of the temperature at which the steel will harden, makes 
it very soft. For ordinary quenching the heat should not go 
above incipient red heat, (600° or 700°, Cent.,) but some kinds 
of steel may require to be quenched two or more times, while 



30 THE WATCH ADJUSTER'S MANUAL. 

Others will be soft after one quenching, even without the slow 
cooling process mentioned. If the latter is used, the tempera- 
ture may be a cherry red, (800° or 900°, Cent.,) the article be- 
ing packed in dry iron filings or dry powdered wood charcoal, in 
a crucible or a cast-iron vessel, closely luted up, and the entire 
pot buried in the ashes. For the quenching process, no such 
packing is needed. 

(59.) Cleaning blackened steel. — When steel has been heated in 
the fire and has acquired a black coating, this oxide can be 
best removed by pickling or leaving it in dilute sulphuric acid 
(i part of acid to 6 or 10 parts of water) till the scale is en- 
tirely removed; wash thoroughly in water to remove the last 
traces of the acid, and carefully wipe dry if the steel is in large 
pieces. In the case of wire, soak in alcohol to absorb the water 
and dry it off. 

(60.) Cleanmg tarnished or colored steel. — When the steel has 
not been so roughly heated as to receive a black coating as 
described, but is merely colored or has a gray surface, it can 
be cleaned by immersing in dilute muriatic acid (acid one part, 
to two parts of water,) till the surface becomes white and clean. 
Next wash thoroughly in water, then in a weak solution of 
cyanide of potassium (saturated solution one part, water 4 
parts,) and finally in alcohol, as before. 

(61.) To preveiit cracking in hardening. — After being annealed 
and cleaned as before described, the steel is ready to be 
worked, with the assurance that it will be perfectly soft, of 
uniform texture and free from hard spots, fit for drawing or the 
finest turning. After being worked into shape, and ready for 
hardening, it is well to again heat it to a blue and let it cool 
slowly, as that is thought to prevent the tendency to crack or 
warp in hardening. It will of course be understood that the 
foregoing treatment of steel is not only for springs, but also 
for the steel used in making balances, and tools, and for all 
similar purposes. 

(62.) Hardening steel. — The method of hardening small arti- 
cles of steel has entirely changed since the first edition of this 
book was published. At that time, the steel was covered in 
some way to protect it from the air; then heated in a coke or 
charcoal fire, and quenched in water or other bath with the 
covering still protecting it. Then came the era of the lead 
bath. The article was heated in a pot of melted lead, in which 
it could be safely left as long as necessary for heating it through, 
as the lead protected it from the air; and, if the temperature of 
the bath was correct, the article could not be overheated, no 



THE WATCH ADJUSTER'S MANUAL. 31 

matter how long it was left in the bath, because it could not be 
heated higher than the bath. The lead bath was a great im- 
provement, and is still a very important aid in ordinary work. 

{(y^-^ The neiv 7nethod of heating. — Within a few years, 
another important change has occurred, especially applicable 
for the treatment of hair springs and other small articles. The 
steel is now heated in a bath of melted cyanide of potassium, 
which protects the steel from the air while heating, in the same 
way as the lead bath, but it has the additional advantage that, 
when the article is removed from the bath for quenching, a 
thin film of cyanide adheres to its surface and protects it from 
the air, without interfering with the hardening, as it instantly 
dissolves off in the water. The oxidation and scaling of the 
surface is avoided, and the tendency to warp and crack in 
hardening is also prevented (102). The cyanide is melted in 
a wrought-iron pot, and its temperature is shown by its color. 
Every part of the article can be heated equally; the thick 
metal block is brought up to a red heat without overheating 
the thin spring coiled upon it. 

(64.) The temperatures used in hardening. — In order to be as 
precise as possible about the temperature of the bath, it is well 
to work in a slightly darkened room, or at least not too light, 
so that the colors can be accurately noted, and do not allow 
the bath to go above the proper heat, which is invariably shown 
by the color, and can be known by consulting the table below. 
It should not be above middle cherry red for cast steel, or clear 
cherry red for shear steel. 

Colors at Red Heat and Upward. 

The following table, compiled by Pouillet, gives the tempera- 
tures corresponding to the different colors of a body raised to 
a red heat: — 



I. 


Incipient red heat 


corresponds to 




525° Cent. 


980° Fahr 


2. 


Dull red 


1 1 




700° C. 


1290° F. 


3. 


Incipient cherry red heat corresponds to 


800° C. 


1470° F. 


4. 


Cherry red 






900° C. 


1650° F. 


5. 


Clear cherry red 






1000° c. 


1830° F. 


6. 


Deep orange 






1100° c. 


2010° F. 


7. 


Clear orange 






1200" c. 


2190° F. 


8. 


White 






1300° c. 


2370° F. 


9. 


Bright white 






1400° c. 


2550° F. 


10. 


Dazzling white 




1500" 


to 1600° C. 2730° 


to 2910° F. 



Frodsham gives the following: — 

11. Red heat, visible by daylight I077° Fahr. 

12. Iron red hot in the twilight 884° F. 



32 



THE WATCH ADJUSTER'S MANUAL. 



(65.) The hardening ajid qtienc/iing bath. — Notwithstanding all 
that has been said about special hardening baths, etc., practical 
men generally are pretty well agreed that a plain water bath 
can answer all purposes as well as any. It should not be ice 
cold, but at about 60° F. If the steel has been properly an- 
nealed and not injured in working, heated uniformly in every 
part but not overheated nor scaled, and so immersed in the 
water as to cool every part as uniformly as possible, the result 
will be entirely satisfactory. After quenching, remove the article 
from the bath, place it at once in alcohol to absorb the water, 
and dry in boxwood sawdust, as usual. If the surface is slightly 
dull, rubbing it with a little rouge will restore the polish. 

Many good workmen claim great virtues for kerosene as the 
quenching liquid. They heat steel springs or other parts 
strongly, rub over with common soap while hot, to protect the 
surface, then heat to a cherry red and quench in a bath of ordi- 
nary petroleum. The steel will not twist, and remains perfectly 
white, ready for immediate annealing, which may be done in oil 
or with tallow, as usual. 

{66.) Tempering steel. — The usual way is to put the article 
in an iron spoon, or any metal capsule or vessel, containing 
melted tallow or oil, and heat it till the oil smokes in a certain 
way, or takes fire and burns off. The following table will indi- 
cate the temperatures and tempers corresponding to different 
grades of smoke and burning, with tallow or linseed oil: 

Tempering Steel in Tallow, Oil or Alloys. 



No. 



Color. 



Pale straw. . . 

Straw 

Straw yellow. 

Nut brown . . 

Purple 

Bright blue. . 

Deep blue. . . 
Blackish blue. 



Adapted for 



Lancets and tools for 

cutting iron. 
Watchmakers' tools. 
Penknives and 

razors. 
Small pinions and 

arbors. 
Large pinions and 

arbors. 
Swords and watch 

springs. 

Watch hair-springs. 



Tempera- 
ture. 


420° 


F. 


450° 
480° 


F. 
F. 


500° 


F. 


530° 


F. 


580° 


F. 


590° 


F. 


640° 


F. 



Alloy fusing at 
same tempera- 
ture. 



Chronometer hair- 
springs. 

g. Boiling linseed oil indicates a temperature of 640° F 
10. Boiling: olive oil 600° F 



7 lead, 4 tin. 

8 lead, 4 tin. 
8i lead, 4 tin. 

14 lead, 4 tin. 

19 lead, 4 tin. 

48 lead, 4 tin. 

50 lead, 2 tin. 
All lead. 



Appearance 
with tallow. 



Vaporizes. 

Smokes. 
More smoke. 

Dense smoke. 

Black smoke. 

Flashes when 
a flame is ap- 
plied. 

Continues to 
burn. 

All burns 
away. 



:s at 196° C. 


385° F. 


• 230° C. 


446° F. 


' 240° C. 


465° F. 


' 270° C. 


520° F. 


' 290° C. 


550° F. 


' 310° C. 


590° F. 


' 320° C. 


608° F. 


• 420° C. 


790° F. 



THE WATCH ADJUSTER'S MANUAL. 33 

Steel can be tempered by heating in an alloy which is kept 
just above the point of fusion. The above table gives the 
melting points of a number of alloys. As soon as the article is 
heated thoroughly, it may be removed from the bath, and al- 
lowed to cool slowly. 

(67.) Other metallic baths for tefnpering steel. — The following 
metallic baths may be used instead of those already mentioned: 

Various Melting Points. 

1. An alloy of i part lead and i part tin (by weight) melts at 196 

2. Metallic tin 

3. An alloy of 2 parts lead and i part tin 

4. Metallic bismuth ... 

5. An alloy of 5 parts lead and i part tin 

6. Metallic cadmium 

7. Metallic lead 

8. Metallic zinc 

and volatilizes if raised to a red heat. 

(68.) Method of teinpering in metallic baths. — The difficulty 
with metallic baths for tempering, is that they are liable to be 
heated far above the fusing points, without giving any indica- 
tion of that fact, and the article may have its temper entirely 
removed. A good way is to dip the (cold) article in the bath 
and at once take it out again. It will of course be covered 
with a coating of the metal which has cooled upon it. Then 
immerse again in the bath till this solid metal has entirely 
melted off and the article comes out perfectly clean and free 
from the alloy. Then allow it to cool. Some kinds of steel 
require to be tempered two or more times to soften them suffi- 
ciently. Such steels are troublesome and uncertain, and had 
better be tempered with the aid of a thermometer (72), 

(69.) Temperijig steel by heatifig in the air. — Another way very 
commonly followed is to heat the article in the air till it takes on 
the color which corresponds to the temper desired. This is a 
tolerably accurate method, but the article is apt to be left brit- 
tle. The color for each temper is given below. 

Colors Below a Red Heat. 

The following table, by Stoddart, shows the tints which cor- 
respond approximately to the various temperatures of a body 
moderately heated, and the uses for which each temper is 
adapted: — 

1. Very pale straw yellow 220^ C. 430° F. ) ^^^j^ ^^^ ^^^^j^ 

2. A shade darker yellow 235 C. 450 r.) 

3. Darker straw yellow 245° C. 470° F. \ Tools for wood andscrew 

4. Still darker straw yellow. ... 255° C. 490° F. \ taps, etc. 

3 



34 



THE WATCH ADJUSTER'S MANUAL. 



5. Brown yellow 260° C. 

6. Yellow, tinged slightly with 

purple 270° C. 

7. Light purple 275° C. 

8. Dark purple 290° C. 

9. Dark blue 300° C. 

10. Paler blue 310° C. 

11. Still paler blue 320° C. 

12. Still paler blue, with a tinge 

of green 335° C. 

(70.) The following table is given by C. Frodsham 




Hatchets, chipping 
chisels, and other per- 
cussive tools, saws, etc. 



the above 



Too soft for 
purposes. 



No. 



Tempera- | 


ture 




430° 


F. 


450" 


F. 


470" 


F. 


490" 


F. 


510" 


F. 


530° 


F. 


550" 


F. 


560^ 


F. 


600° 


F. 


to 




660° 


F. 



Colors. 



Faint yellow 

Pale straw 

Full yellow 

Brown yellow 

Do., with purple spots. . . . 

Purple 

Bright blue 

Full blue 

Dark blue, verging on pale 
black, technically termed 
white. 



Adapted for 



Lancets, 

A little softer. 

Razors and surgeons' instruments. 

Small pinions and arbors. 

Cold chisels and shears for cutting 

iron. 
Large pinions and arbors. 
Swords and watch springs. 
Chronometer and watch balance 

springs. 
Chronometer balance springs. 



(71.) "Steel may be tempered in a metallic bath, in linseed 
cr salad [olive] oil, heated to the proper degree. The colors 
are very imperfect indications of the requisite temperature. 
Perfection of temper depends not only upon the temperature, 
but upon the time occupied in the operation." 

10. Linseed oil boils at 640° F. 

11. Shellac began to soften at 180° F. 

12. " was soft and plastic, but showed no signs of fusion at . 212° F. 

13. ** boiled up at above 300° F. 

14. Water boils at 212° F. 

15. Alcohol " 174° F. 

(72.) Tempering with a thermometer. — All of the foregoing 
ways, although they can be safely followed after sufficient ex- 
perience, are ordinarily somewhat uncertain and clumsy. The 
best way is to temper in a bath of melted paraffin, sweet oil, 
cyanide, or a metallic alloy, (according to circumstances,) 
heated to the proper degree, and kept there by using a chemical 
thermometer or pyrometer. Such a thermometer graduated 
up to 650° or 700° Fahrenheit will cover all temperatures that 
can possibly be required for any tempering operation, and will 



THE WATCH ADJUSTER'S MANUAL. 35 

only cost a couple of dollars. Then you will know just what 
heat you are using, without any guesswork about it, and will 
be able to obtain definite and uniform results. One kind has a 
double glass stem, with a paper scale of figures within the 
outer tube. Others have a single stem, with the figures cut on 
it. The former is clearer, but the latter is more durable. By 
making an ink-mark at the proper place before you begin, you 
can see when the desired temperature is reached without any 
trouble. As soon as that occurs, remove the heat, or remove 
the oil or other bath from the heat, and let it cool down to 
about boiling water (212°) before taking out the object, and it 
will be perfectly tempered. The cyanide bath can also be used 
for tempering steel, at any of the temperatures between its 
melting-point and the upper range of the thermometer; it 
acts to dissolve all oxide off steel or iron, but acts more power- 
fully upon some of the other metals and alloys, and so injures 
the surface of the latter. 



CHAPTER VI. 

Making Cylindrical or Helical Springs. 

(73.) Different forms of springs. — There are two principal 
forms for hair springs: the flat spiraL either plain or with the 
Breguet curve, and the cylindrical or helical. The latter is 
adapted for chronometers, and the former for most pocket 
watches. There are many other forms, not often employed, 
as the spherical, which is largest in the middle and taper- 
ing down toward each end, making it globular in form. 
These are very troublesome to make and set true, and have no 
practical advantage over the helical form with proper terminal 
curves. Another method is to make half of the wire in the 
helical form and the rest is coiled up in the flat form at the end 
of the helix. This is called the duo-in-uno spring. Then there 
is the reversed helix, being, in effect, a helix broken in two in 
the middle, and the two ends pinned into a stud in such a way 
that the upper half of the spring coils up while the lower half 
is uncoiling, and vice versa. It can, of course, be made in one 
piece. This is difficult and unreliable. The same object is 
accomplished with flat springs, by using two of them, so at- 
tached that one coils up while the other uncoils, as above 
stated. But no form of spring has yet been tested which pro- 
duces any better effects than can be obtained from the helix or 
the spiral, by proper manipulation. 



36 THE WATCH ADJUSTER'S MANUAL. 

(74.) Advantages of the different forms. — There are good 
workmen who claim that a flat spring cannot be made iso- 
chronal — which, in view of innumerable instances to the con- 
trary, is as ridiculous as the claim that the spring-detent or 
chronometer escapement is, per se, superior for keeping time to 
a detached lever escapement equally well made — a point which 
I shall touch upon hereafter. Theoretically, the helix, with its 
coils of equal diameters, is superior to the spiral; but practi- 
cally, the average of the effects of the numerous coils of differ- 
ent diameters is equal to that of a spring with equal coils of an 
intermediate diameter. And a spiral spring with its outer end 
returned by a properly formed terminal curve is fully equal to 
a helical spring, for pocket watches; but for marine chronom- 
eters it is better to make the spring in the helical form, on 
account of the large size of the wire required for their heavy 
balances. As both forms are good, I will describe the mode of 
making each. 

(75.) Making helical springs. — For the helical spring a cylin- 
drical brass or German silver block is made, and shallow 
grooves cut in its exterior surface, by a small screw-cutting 
lathe or otherwise, having the exact shape the spring is desired 
to take. The wire is then coiled tightly in these grooves, and 
each end is fastened by screws or pins. Instead of a grooved 
block, a smooth one can be used, and a narrow extra wire coiled 
up with the spring wire, to keep the coils at a uniform distance 
apart — the extra wire being between the coils. It is not really 
necessary to have the extra wire, as the spring wire can be 
coiled by itself, and if evenly done the coils will open out 
enough in the bluing to avoid coming in contact with each 
other while vibrating. The spring is of course drawn tight 
and even on the block, before tempering. The object of 
using German silver blocks is two-fold: If of steel, they would 
be liable to warp more or less by hardening^-'and communicate 
an irregular form to the spring, which is, of all things, to be 
avoided; and a steel block will scale to some extent by the 
hardening process, and lose the perfect accuracy of its grooves 
— whereas a good brass or German silver block can with care 
be used many times. The block on which the cylindrical 
springs are hardened should be hollow, so that it will cool 
quickly. Its thickness should be no greater than will give 
sufficient rigidity and strength. The thickness is generally 
from one-eighth to one-sixth of the total diameter of the block, 
or about xs" ^*^ i ^^^^ thick. 

(76.) Setting helical springs. — If the spring is given spring 



THE WATCH ADJUSTER' S MANUAL. 37 

temper by drawing and rolling, and is to be simply blued and 
"set," hold the block with the spring upon it in the flame of 
the alcohol lamp, turning it constantly, and heating slowly and 
evenly, till it acquires the proper color, then let it cool. One 
bluing is sufficient for a rolled siring, but coloring a hardened 
and tempered spring is a very different matter. 

(77.) Harde7iing helical spriiigs. — If the spring is to be 
hardened by fire, it is sometimes wrapped in thin sheet copper 
or platina foil, while wound on the block, fastened with binding 
wire or folded over the ends, having been previously well 
daubed over with common soap, softened by warmth, not 
moisture, and mixed with wood-charcoal dust, which largely 
protects it from scaling and coloring by the heat, by keep- 
ing it from the air. When so wrapped up it must be hardened 
in water. But most workmen simply slip the block and its 
spring into a brass, copper, or iron tube, or even a common 
clay pipe bowl, and fill it around and over the block with fine 
wood-charcoal dust, well shaken down to fill all the interstices, 
and entirely exclude the air while the wire is being heated. A 
small piece of steel wire must be so placed that it can be occa- 
sionally taken out to judge of the heat, as charcoal packing is 
a very poor conductor of heat, and very deceptive to the inex- 
perienced. Very fine silver filings have been proposed, being a 
good conductor, but I do not know that this has been tried. 
Animal charcoal is also used, but it makes the spring very hard 
and difficult to form the terminal curves. 

(78.) The whole must be carefully heated in a charcoal fire: 
to a cherry red, but no higher, and, as soon as it reaches that, 
the block with its spring is emptied into oil or water — the prefer- 
ence being for oil, unless the block is wrapped up as stated^ 
above, v/hen it should be quenched in soft water. The proper 
temperature for the quenching bath is about 60° Fahr., as that 
is found to give sufficient hardness without danger of causing 
the steel to crack. But if the wrapping is at all thick, a greater 
degree of cold will be safe, and in fact necessary — but that is 
to be avoided. 

(79.) Improved juethod of hardening helical springs. — The proc- 
ess described is the one usually followed. But the modern 
method would be to coil the wire on a German silver or copper 
cylinder and secure the ends by screws as described, heat in a 
cyanide bath [6^) and quench in water, then temper in cyanide, 
(72), after loosening one of the screws, and drawing the spring 
tightly upon the block; clean in acid, (60,), and finally color it. 
The usual way of tempering is as follows. 



38 THE WATCH ADJUSTER'S MANUAL. 

(80.) Tetnpering helical spriiigs. — If the spring has been hard- 
ened in oil, it is now drawn down to a straw color — if in 
water, to a purple — then removed from the block and polished 
inside and out, edges and all, with a stick and fine oil-stone 
dust or "sharpe," again fastened tightly on the block as be- 
fore, and the color brought down to a rich dark blue. This, 
however, is a matter which depends somewhat on the quality 
of the wire used, and can only be fixed by testing your sample. 
Some steel will be as hard and elastic at a dark blue as another 
sample will be at a straw color. The aim should be to stop 
just short of brittleness, so that a piece of the tempered wire 
may, with care, be bent cold to a right angle around your 
screw-driver, or a round broach, but would snap off if it was 
bent carelessly or over the square edge of your pliers. If the 
spring is to be used white, it should be brought to the proper 
temper before polishing. Others temper the spring by heating 
in an oil or tallow bath, as described in section {66). When 
dried after hardening, they draw the spring tight on the block 
(79), and temper in oil to a blue, then clean and polish as above, 
ready for coloring or " bluing. " In forming the terminal curves 
the hardened spring must always be bent by heated tools, a sub- 
ject I shall treat on hereafter under the head of isochronism. 

(81.) In coloring a spring, it is not always necessary or even 
advisable to go by the color of the spring itself, as any piece of 
steel on the block or plates will do just as well. But there are 
certain precautions to be observed which are not necessary with 
larger articles of steel, because here even the slightest varia- 
tion of the temper affects the action of the spring. Supposing 
the color should be a dark blue, if the mass (spring and block, 
or plates,) has been heated rapidly, the coloring must be stopped 
sooner, or at a lighter shade, say a purple or a reddish-brown; 
or else it will go too far before it stops; while if it has been 
heated very slowly, it may be carried to the exact shade 
desired. 

(82.) The color-piece. — The screw or piece by whose color we 
are guided should be hardened, as hard steel colors with less 
heat than a soft piece would do, and consequently there is less 
danger of reducing the temper too low. Some makers color or 
heat their springs once only; others clean the bluing off the 
color-piece and blue again; some even heat their springs five 
or six times. My own opinion is that if the spring has been 
properly made, hardened, tempered and polished, one bluing 
should be sufiicient. But if it has scaled in hardening, or 
minute imperfections, roughness or cracks are feared, it will be 



THE WATCH ADJUSTER' S MANUAL. 39 

safer to heat twice, but never more than three times. If the 
spring, after that, breaks under the test named in (80), it may 
be considered imperfect, unless it was packed in animal char- 
coal, when it will break even after the sixth bluing if bent cold. 
Such a spring, if smooth and perfect, may be blued three times, 
and will be sufficiently soft. It is understood, of course, that 
the color-piece requires a greater heat to bring it to a blue the 
second time than when it was hard, so that in reality it will be 
reduced to a lower temper or made a little softer at each blu- 
ing, although the color is exactly the same each time. This 
is also the case with the spring; but this need not be whitened 
after each heating, nor even loosened (if on a block) till done. 
But if the color-piece was soft at the start, the temper will not 
be reduced any lower by bringing it to the same color several 
times. 

(83.) Another point is to avoid what are known as false 
colors. The color-piece, or some part of it near the middle of 
the whole mass, if practicable, is first ground off with the oil 
stone, or even Scotch gray. This bright spot must then be 
slightly dimmed again, by rubbing the finger over it once or 
twice before coloring, for the degree of temper cannot be 
closely judged from the color of a very bright piece, as will be 
found by trial. In coloring flat springs, as hereafter directed, 
the color-piece may be screwed in the center of the plates, 
holding them together, or in the center of the spring-cover of 
the bluing-pan, and the heating should be very slowly and 
evenly done, the center of the hair-spring resting just in the 
center of the pan, and the cover also being central. 

(84.) Before leaving the subject of coloring springs, I may 
add that it furnishes us a ready means of discovering whether 
they are equally hardened or not. For instance, if the wrap- 
ping (77) touches the spring in some places and does not in 
others, the former will be harder when quenched. So if the 
wrapping is lapped on one side and thicker than on the other, 
the spring will not be so hard in the former places as in the 
latter. This we may test after cleaning the block, but before 
loosening the spring, by arranging the block to revolve freely 
between the centers of the " turns," then suspending a trough or 
half cylinder of sheet copper under it, reaching up on each side, 
protecting it from the blaze, but leaving the upper half exposed 
to view. Now apply the heat to this copper trough, which in 
turn will communicate it to the block, and the latter will be 
heated more evenly than could be done by applying the blaze 
directly to it. The block must be constantly turned by a piece 



40 THE WATCH ADJUSTER'S MANUAL. 

of peg wood, and the lathe centers loosened up when it ex- 
pands. When the spring reaches a purple in its darkest part, 
take away the lamp and trough, still turning the block till it 
has cooled somewhat, when an examination will reveal any in- 
equality of temper. Any soft places will be indicated by a 
lighter color, in spots or streaks, according to its cause. Even 
the course of a carelessly applied binding wire may be traced. 
Should any such appearance be found, it must not be passed 
over as a slight matter, for it is proof positive that the spring is 
incapable of fine performance, and it must either be rehard- 
ened, or, if it has been scaled in the first hardening, it must be 
rejected entirely and a new one made. 

(85.) Dia??ieter of springs. — The proper diameter for a hair 
spring is a matter of calculation in new chronometers and 
watches, but helical springs are generally one-half the diameter 
of the balance. But a certain length in proportion to its thick- 
ness is indispensable to its free action, and if it is found that 
there is not room for that length of a helical spring, the coils 
being of the above-named diameter, then a spring with larger 
coils must be made, to secure the necessary length of wire. 
But the repairer should generally be guided by the old spring, 
if it yet remains, remembering that the new spring, when fin- 
ished, will have expanded a little larger than the grooves in the 
block, or its first size before being hardened. If your wire is 
not of the same stiffness as that of the old spring, more or less 
coils than the old one had must be used, to get the same strength 
of spring. But generally the old spring should be copied in all 
respects, unless there is good reason to believe that it was never 
satisfactory. 

{^6.) The number of coils for a helical spring is given in sec- 
tion (397), but it is well to make one or two extra coils, to 
allow for testing the temper at the ends, etc., after which the 
superfluous length can be broken off. A rather long spring is 
better than a short one, especially if it is somewhat soft, as the 
angle of flexion, and the consequent danger of setting by use, 
are less. A spring should be thin and hard, rather than thicker 
and lower tempered, both being of the sam.e strength. For 
the former will maintain the motion of the balance longer 
(without additional impulse from the hand or the movement), 
and consequently a watch with such a spring will be less affected 
by difference in the motive power, or friction, poor oil, jarrings, 
etc. The less the number of coils the harder the temper should 
be, and, conversely, the softer the spring the longer it must be. 
Hardened springs are less liable to be affected by magnetism 



THE WATCH ADJUSTER' S MANUAL. 41 

than soft ones, and are to a great extent, but not entirely, free 
from the deterioration or loss of force to which all springs are 
more or less subject by constant action, even when the flexion 
does not approach the limits of their elasticity. The well- 
known phenomenon of hardened springs slightly accelerating on 
their rates, for a few months after being fitted, is an example 
of this change of condition in the reverse direction. In this 
case the springs lose a portion of their excessive initial hardness, 
and gain in pliability and elasticity. After attaining their 
greatest degree of elasticity they remain nearly constant, while 
the deterioration of soft springs is comparatively rapid. 

(87.) Making the ter}ni7ial curves will be described under the 
head of Isochronism, as it is properly a part of that adjust- 
ment. The foregoing directions will give a clear idea of the 
process of making helical springs, and will secure a better un- 
derstanding of subsequent operations. Furthermore, the work- 
man who proposes to fit a helical spring in a chronometer will 
generally find it necessary to make one to suit. Hence instruc- 
tions upon that operation must include the making of the spring, 
as already described. The making of palladium springs will 
be described in sections (100, loi), and of gold springs in sec- 
tions (98, 99). 



CHAPTER VII. 

Making Flat Spiral and Breguet Springs. 

(88.) The usual method. — In the next chapter I have given 
the modern improved process followed by the American spring 
makers, and will now describe the method usually pursued. 
Flat spiral springs can be bought ready-made, of almost every 
strength and quality, so that a suitable one can generally be 
readily selected from a fair stock of them, and thus save time 
and labor. But cases occasionally occur when nothing suitable 
can be got, and a knowledge of the operation of making one 
precisely as wanted will be very useful. The selecting and pre- 
liminary treatment of the spring wire are given in Chapter V. 

(89.) The spring windijig tool consists of a sort of box like a 
mainspring barrel, with flat bottom, and sides turned out verti- 
cal to the bottom; the cavity is of the diameter required for 
holding the required number of coils of spring. A cover fits 
over the box, with a portion fitting into the cavity, and is held 
in place by two screws or otherwise. The side walls of the box 
have openings through which the wire is wound into the box. 



42 THE WATCH ADJUSTER'S MANUAL. 

These openings are not radial, but nearly tangential, to facili- 
tate the entrance of the wire. Both the box and the cover 
have a central hole into which fits the winder. 

(90.) The winder. — This is slightly like a steel barrel arbor, 
having an outside shoulder which prevents it from entering too 
far. The part which passes through the box has as many slits 
sawed down into it as there are springs to be wound, whether 
two, three or four, and also has a central hole, tapped for a 
screw. The slits are sawed down to the level of the bottom of 
the cavity, and the circumference between the slits is " snailed," 
to correspond to the thickness of wire used, so that each wire 
will have a true spiral form from its slit onto the wire from the 
next slit before it. 

(91.) The winding. — If four springs are to be wound into 
the box together, the space between the coils will of course be 
equal to the thickness of three springs. The space between the 
cover and bottom of the box is equal to the width of the spring 
wire. The wire being cut into lengths suitable for springs, the 
ends are put through the openings in the box, and fitted into 
the slits of the winder, and the central screw secures them in 
place. The wires are then carefully wound into the box, as 
closely together as possible and without twisting, till the box is 
full. The screw is then removed from the winder and the inner 
ends of the springs freed so that the winder can be taken out. 
Mr. Logan then takes out the cover and substitutes what he 
calls a "cap," without any hole in it. That is better than the 
usual plan, which is to screw the cover down tight, to press the 
springs perfectly flat, and then stop the holes with a mixture of 
soft soap and wood-charcoal dust, to exclude the air while 
hardening. In making cheap springs, they are merely heated 
till a piece of steel laid on the box becomes blue, to cause them 
to " set" and remain in that form. 

(92.) Hardening and tempering flat spiral springs. — To harden 
them, they are heated to a cherry red, usually in a charcoal fire 
or a lead bath, (but the cyanide bath is preferable,) and 
quenched in cold water. The box is then boiled in oil to tem- 
per the springs — the usual rule being to temper to a blue. 
They are then taken out of the box, separated and cleaned in 
dilute hydrochloric or sulphuric acid — the former being preferred, 
as the latter is apt to leave dark marks on the surface. For de- 
tails on any of the above points, see Chapter IV. 

The box and cover may be made of German silver, brass or 
copper. 

(93.) Polishing the springs. — If the springs are made of good 



THE WATCH ADJUSTER' S MANUAL. 43 

Steel, poUshed and clean when wound in the box, hardened in 
the cyanide bath, tempered either with cyanide or in oil and 
then cleaned with hydrochloric acid as described above, it 
should not need any polishing. But when it does, use a stick 
with a conical end to hold the spring upon, and scour it with a 
stiff brush, as a tooth-brush. The stick is held in the left 
hand, its point in the center of the spring, which is stretched 
down over it into a shape similar to that of a hoop skirt, and 
kept in that position by the thumb resting upon it while the 
outsides of the coils are being polished. The insides of the 
coils are polished by sharpening a piece of peg wood and forc- 
ing the spring into the same shape, while resting it on a flat 
piece of cork, rubbing it by moving the stick in both an oscil- 
lating and lateral direction, very carefully, to avoid bending 
the coils. The edges are polished by rubbing the spring 
around on a piece of smooth paper, by means of a cork pressed 
gently upon it. In all cases the polishing powder should be 
plentifully supplied. Springs should not be polished any more 
than necessary to obtain a clean smooth surface, lest some parts 
should be reduced more than others and cause irregular action. 

(94.) Coloring the spring. — After being well cleaned, it is laid 
in the bluing-pan and heated till it acquires the proper color, 
and is then thrown off to cool. If the spring does not make 
good contact with the pan in all its coils, while coloring, a 
heavy plate is laid over it, or held down by a spring, or even a 
screw. Of course, the under surface of the plate and the sur- 
face of the pan must be perfectly flat. 

(95.) Making Breguet springs. — The Breguet spring is ordi- 
narily made first as a flat spiral, and tested in that form to find 
the proper length for timing the watch. The time, or what is 
the same thing, the number of vibrations, given by a spring de- 
pends on its length between the stud and collet, and not on its 
form. Consequently, when the length suitable for the watch 
has been found, the curve can afterwards be formed in such a 
way as to make the long and short arcs equal in time. This 
could not safely be done before testing, because the adapta- 
bility of the spring and the proper place for the elbow could not 
be known till after this trial. The making of the elbow and 
shaping of the curve will be described under the head of Iso- 
chronism. 

(96.) Hardening the terminal curve in for^n. — For more than 
thirty years some workmen have made the elbow on the Breguet 
spring, and then hardened it with both the main and supple- 
mental coils already at their proper levels, but the terminal 



44 THE WATCH ADJUSTER' S MANUAL, 

curve was not fully formed till the final fitting of the spring in 
the watch. This could of course be done when the required 
size and number of coils and the proper place for the elbow 
were already known, as might be the case in factories where 
large numbers of movements were made alike, after a model 
known to be correct. Mr. Logan, at the Waltham watch fac- 
tory, made two important improvements in the art. He en- 
tirely dispensed with the elbow, by causing the supplemental 
coil to rise gradually to its proper height, and he hardened and 
tempered the whole spring in its final form, including the spiral 
body, the incline and the terminal curve, thus avoiding any 
distortion or straining of the metal at the elbow, and securing 
a curve hardened in form. 

(97.) The means for accomplishing this are very simple. 
The spring box is made to contain the proper number of coils 
of the spiral, as usual. The spiral openings are tangential, and 
from the opening is cut a groove, in a manner similar to that 
on a fuzee, on the outside of the spring box, curving upward 
and then inward, precisely as the spring is desired to be. The 
spring wires being wound into the box till it is full, the ends 
outside are fitted tightly in the grooves and secured in position, 
after which the hardening and tempering are performed as for 
the ordinary spiral form. It is obvious that any desired curve 
can be cut in the spring box, and the most difficult and perfect 
forms can be reproduced with certainty. 

(98.) Making gold springs. — At one time gold springs seemed 
likely to be extensively used, but long experience has shown 
that they are not so reliable as steel. The alloy is more difficult 
to work properly than that metal. The gold is alloyed with 
copper or silver, (generally, 18 K,) and its hardness is greater 
in proportion to the amount of the alloy. It is also made 
harder by drawing and rolling, but is very brittle. Instead of 
hardening and tempering by heat, as for steel, they are made 
elastic by annealing, in boiling oil, or by coiling on a block or 
plate, and heating to a blue but no higher. Cylindrical springs 
coiled on a block as above, are put in a metal tube, with a 
steel cover or a steel screw in the cover to indicate the temper- 
ature. The tube is heated till the steel becomes blue, then 
removed from the flame and allowed to cool slowly. Flat 
springs on a steel plate are annealed in a similar way. 

(99.) Objectio?is to springs of gold. — Its expansibility in heat 
being greater than that of steel, it requires heavier adjusting 
screws in the balance, thus introducing a train of evils which 
more than offset any advantages over steel in respect to being 



THE WATCH ADJUSTER' S MANUAL. 45 

free from liability to rust or to be affected by magnetism. If 
carefully prepared and worked it retains its elasticity for a long 
time. But being heavier than steel, a gold spring is more 
liable to tremble and sag. The loss of elastic force when 
heated is greater than that of steel, and as that is really the 
greatest failing in steel springs, it is still more objectionable in 
those of gold. At present the use of gold springs is practi- 
cally limited to the unlocking springs of the detents in chronom- 
eters. 

(100.) Making palladium springs. — Springs are now made 
from different alloys of palladium. They do not become tar- 
nished by exposure to air, sulphurous acid or sea-water. Their 
elasticity is imparted by wire-drawing and rolling, and can be 
made equal to that of steel tempered to a blue. They do not 
become distorted in form by heating, and on cooling recover 
their original elasticity. Their loss of elastic force when 
heated is less than that of steel, but the precise amount has 
not been determined. Their expansion by heat is also some- 
what less than that of steel. Their limit of elasticity is less 
than that of hardened and tempered steel springs, and they are 
more easily pulled or drawn out of shape. They must be bent 
with great care, lest they be bent too much and injure the tex- 
ture of the metal at that point; they are easily marred by 
blows or pressure. Not having their molecular condition 
changed, as occurs when steel is fire-hardened, but being in a 
condition similar to steel tempered by drawing and rolling, 
they must be classed with soft springs and handled accord- 
ingly. But it has been found that palladium springs accelerate 
on their rates (381) less than those of hardened steel, and 
the middle temperature error (614) is also less. They are 
heavier than steel, and therefore sag more. In making them 
into the Breguet form, greater space must be allowed between 
the body and the terminal curve to avoid possible contacts. 
The curves are easily formed with the tweezers. 

(toi.) Palladium is a silvery white metal, non-magnetic, 
heavier than silver or lead, with a hardness equal to that of 
wrought iron. When heated sufficiently in air it oxidizes on 
the surface and becomes blue. The compositions of the alloys 
used for balance springs are not known. Springs of the differ- 
ent alloys can be obtained already made, in either the spiral or 
cylindrical form, or the spring wire, ready for coiling, can be 
purchased in London, where it is drawn. Whether palladium 
springs will • prove to retain their elasticity and other proper- 
ties as long, or nearly as long, as those of steel is yet uncer- 



46 THE WATCH ADJUSTER' S MANUAL. 

tain. But strong claims are made for them, and they certainly 
have a promising outlook. They are now being used quite 
largely, and by makers of the finest grades of timepieces, so 
their merits and demerits must soon become positively known. 
Thus far, they are the only rivals of steel. 



CHAPTER VIII. 
The Modern American Method of Making Hair Springs. 

(102.) Mr. A. J. Logan has kindly written a description of 
the method of making the world-renowned American watch hair 
springs, hardened and tempered. As the Logans have probably 
made more watch hair springs than all the other makers in the 
world put together, all of them high-class springs, a statement 
of the method employed must be regarded by the trade as 
of unusual interest and value. It is as follows: — 

(103.) " Below you will find answers to your queries regarding 
the making and tempering of hair springs. 

ist. The spring should be coiled in a copper box, which 
should be turned out perfectly true, the right diameter for the 
springs. Four springs are wound up together in the box, by 
a special tool made for the purpose. This done, the tool is 
taken out, and a cap that is also turned true is put on to fit 
into the box, then forced down very tightly to keep the springs 
flat. Two boxes are then put together with the caps facing out, 
and wound together very tightly with binding-wire. They are 
now ready for hardening. 

2d. To harden, heat cyanide of potassium in a wrought-iron 
pot, (No. I,) to a cherry red heat, put in the boxes, heat till 
they come to a red heat, cool in cold water. 

3d. To temper, heat another pot (No. 2) to a low red heat; 
dip the boxes in the cyanide and take out quickly; then put 
them back in and leave them in till all the cyanide is melted off; 
then cool them in water and you obtain the right temper. 

4th. The springs are then taken out of the boxes and picked 
apart, great care being taken not to put them out of true. 

5th. Clean the springs with chemically pure muriatic acid 
one part and water two parts, swill them well with water, then 
put them in cyanide water to kill all traces of acid, then into 
alcohol, and dry with sawdust. 

6th. Draw down to a straw color, on a steel plate over a gas 
stove; then remove the color, using the same process as de- 
scribed in No. 5. 



THE WATCH ADJUSTER'S MANUAL. 47 

7th. Then they are put over a gas stove and drawn to a blue, 
on a steel plate. 

8th. The number of coils, in flat spiral springs, mostly used 
for i8-size American movements is 15. Some factories use 14 
coils for i8-size movements. In small springs, 13 or 14 coils 
are used. All flat springs are pinned in even coils, to get the 
best effect. 

9th. The numbers of coils used in the Breguet spring is 13%, 
for all sizes. The % is for the over-coil, which is curved to 
the center and makes it equal to 14 coils. 

loth. By hardening and tempering with cyanide, the over-coil 
needs no covering, and when cleaned with the acid it is all 
right for bluing. 

nth. I do not cut blocks to order for making Breguet 
springs with the over-coil hardened and tempered in shape. 
The patent is now owned by the American Waltham Watch Co., 
and I only make them for that company. The other companies 
form the over-coil with tweezers, like the samples I sent you. 
I have made tweezers for nearly all of them. With a little 
practice, the over-coil can be made very accurately and quickly. 

The information here enclosed has cost me thousands of dol- 
lars and years of experience. Hoping it will be an addition to 
your book, Yours respectfully, 

A. J. Logan, 
Waltham, Mass." 

(104.) The American Waltham Watch Company gives the 
following details: 

" Dear Sir: — In reply to your letter to Mr. Fitch, relating to 
replies to certain questions concerning the manufacture of 
Breguet hair springs. . . . For your further information we 
will say that we make substantially the same number of concen- 
tric coils (14-15) in all sizes of springs. (Q. i) 

We make by far the larger number with gradual curve to 
over-coil, but for the high grade movements we use the Phillips 
curve. (Q. 2) 

The proportions of thickness to width of our springs are i to 
4, and I to zYz. (Q. 4) 

Our over-coils make about ^ of one turn. (Q. 5) 

We harden and temper in same form. (Q. 6 and 7). 

Yours truly, 

Amn. Waltham Watch Co., 

E. A. Marsh, Asst. Supt." 



48 THE WATCH ADJUSTER'S MANUAL. 

(105.) Number of coils m Breguet hair springs. — It will be seen 
from the foregoing that the American watch companies do not 
follow the usual rule to give the Breguet spring about 50 per 
cent more coils than the fiat spiral, but use the same number of 
coils (14-15) for both forms. As they use the same size of 
spring wire for both forms, it would not do to make the Breguet 
spring longer than the other form, as the middle coils would 
then sag and tremble too much. Some may claim that a short 
spring cannot come so near being theoretically isochronous as 
the long one would be, but it is on that account more practi- 
cally isochronous, (660,) and is therefore able to be more widely 
adjusted and correct greater errors, and so give better satisfac- 
tion than the long one. This fact was doubtless ascertained by 
many practical trials, but it is strictly in conformity to the the- 
ory suggested for the flat spiral spring in sections (556, 558). 
Inasmuch as the over-coil enables the spring to expand equally 
on all sides of the center and avoid side pressure, if it can also 
be made perfectly isochronous there would seem to be no good 
reason why that number of coils should not be sufficient. It is 
well known that the American watches can be isochronized as 
closely as any others, and closer than the majority of other 
adjusted watches. As results are always the best guides, it 
follows that that number is sufficient for all purposes. On ex- 
amination of various movements, it appears that they some- 
times vary from that number. The following instances may 
be cited, giving the makers, sizes, numbers of the movements 
and length of springs from the collet to the stud: 

Waltham, 6^ S, No. 6,011,117, n^ coils. 
" 6^ K, " 5,746,501, 12 coils. 

Elgin, 6^ No. 4,777, 33°, ^iV^ coils. 

" 16% 114, No. 5,502,264, 14^ coils. 

Here is a range from 11^ to 17/^ coils, from which we see 
that the exigencies of the isochronal adjustment are the final 
arbiters as to the number of coils required, and that it is im- 
possible to specify any particular length of springs which will 
always be isochronous. 

(106.) Further improvements suggested. — As is stated in Part 
Sixth (560) the effect of short springs is to give greater differ- 
ence of rate between the long and short arcs than long springs, 
and thus enable them to correct greater errors caused by 
change of positions, frictions, etc. In the American springs, 
from the method of their manufacture, the distance between 
the coils is the same from the center to the outside, the effect 
of which is to reduce the difference between the long and short 



THE WATCH ADJUSTER' S MANUAL. 49 

arcs to a minimum. It is known that if the distance between 
the coils increases from the center to the outside of the spring, 
the difference between the long and short arcs is made greater, 
(574,) and it can of course correct greater position errors than 
an equidistant spring could. For watches which are not 
to be adjusted, an equidistant spring would be preferable, but 
the other kind would be better in watches which are to be 
closely adjusted, and would obviate the necessity of making 
such changes in the lengths of the springs, as before men- 
tioned, (105,) and they could also be adjusted more closely. 

(107.) How to make them. — By the ordinary method of making 
hardened and tempered springs, the coils are necessarily equi- 
distant. When springs are not hardened and tempered, but 
wire-drawn and rolled, and then set in shape by bluing, the 
coils open out and become much further apart at the outside 
than at the centre. But the demand is for hardened springs. 
I would therefore suggest the following method of making such 
springs as I have recommended: First, draw and roll the wire, 
wind the springs and set them by bluing, as described. By 
this process two springs would be made at once, and might be 
in one piece, connecting through the winder at the center. 
Second, take these springs, having the shape we desire but be- 
ing still "soft," clamp them between two perfectly flat copper 
or German silver plates, and harden and temper them in that 
shape in the usual way (92, 103). Two pairs of plates with two 
springs between each pair could be clamped together or held 
by binding wire, and hardened and tempered together, and the 
springs then cut apart at the center. One of the plates could 
have a slight boss at the center (to hold the springs central) 
fitting into a hole in the other. The cost of manufacture in 
the factories would not be sensibly greater than for the equidis- 
tant springs, but any one who will compare the springs will find 
the former far superior to the others for isochronal purposes, 
either for the Breguet or the flat spiral form. This method of 
making such springs can be followed even by the ordinary 
watch repairer, who wishes to fit in one of the best possible 
form and kind. 

4 



PART THIRD. 
WATCH BALANCES. 



CHAPTER IX. 
Balance Making. 

(io8.) Making a plain balance. — The best material for a plain 
balance is gold. Although its expansion in heat is somewhat 
greater than that of steel, it is not liable to rust. or be affected 
by magnetism like steel. The making of the balance presents 
no special difficulties to the workman, except the cutting out to 
form the arms. The plate, whether of steel or of gold, (hav- 
ing been well hammered and made hard and elastic, if of gold,) 
is made smooth and flat on its under side and cemented to 
another plate of brass or zinc, then centered in the lathe, and 
the whole surface of the gold is turned off, (the cutter being 
sharp and taking off very thin cuts,) and made smooth and flat, 
ready for crossing out the arms. 

(109.) Crossi?ig out. — Put it on the dividing plate, and mark 
the positions of the arms and their width. They must of 
course be at exactly equal distances apart. Also mark the 
inner edge of the rim — the outer edge can be turned out in the 
lathe. The best way to cut out the arms is to rest the (dou- 
ble) plate against a block of wood and drill a series of holes 
along the sides of the arms, rim and boss, of such size that 
their peripheries will come barely short of touching the marks, 
to allow for finishing. Drill the holes through the gold, but not 
through the brass, or zinc, to avoid producing any burr outside, 
as that would prevent your holding the plate flat while drilling. 
If the back plate is of zinc, you will know when the drill is out 
of the gold, by the shavings being all white. When the holes 
are all drilled, remove the balance from the zinc plate, and 
separate the metal. The finishing is easy, being careful to 
avoid bending the arms. If they become stretched and too 
long, carefully hammer the rim to bring them level. Then 



THE WATCH ADJUSTER'S MANUAL. 51 

shape and polish the rim, etc. For a screw balance, see section 
(no). 

(110.) Maki7ig a compensation balance. — The compensation 
balance of ordinary construction consists of a steel center-bar 
carrying a circular compound rim, which is cut into two or four 
sections, each having one free end and the other end attached 
to the center-bar. This rim is composed of two metals, which 
are unequally affected by heat and cold, usually steel and brass. 
The first balances of this kind were made by fastening the 
steel and brass strips together by rivets at frequent intervals, 
and afterwards they were soft-soldered together. Next they 
were united by hard-solder, but at present they are generally 
united by melting the brass upon the steel. 

(ill.) Making a balaftce. — In making this balance, a piece of 
the best cast steel is selected, a hole of proper size drilled through 
the center, it is then mounted on an arbor and turned perfectly 
flat on both sides and on the edges, which should be parallel 
to the sides of the center-hole and at right angles to the flat 
sides. We then have a round piece or disc of steel, of the thick- 
ness of the rim of the proposed balance, and of the exact diame- 
ter to be given to the steel part of the rim. The brass is then 
either melted on the outside, or a piece of brass is stamped, or 
turned out, of the right size, and soldered on. Or a ring of 
drawn brass (to get a fibrous texture) is fitted to the steel. 
Some prefer one method, some the other. But there is proba- 
bly but little difference between the products of each, when 
equally well made. 

(112.) Uniting the metals by fusion. — When the brass is to be 
melted on, the hole in the center of the circular steel disc is first 
filled up with plumbago, pipe clay, or even fine chalk pressed 
in wet and allowed to dry. Some turn out a plug of slate pencil 
to fit the hole perfectly, and many other means are employed to 
prevent the melted brass from entering the hole during the pro- 
cess. It is indispensable that this hole remain unaltered, as 
upon it depends the truth of all the parts and the equal action 
of the segments when finished. The outer edge of the disc 
must be perfectly clean, to secure a perfect union and adhesion 
of the metals throughout the whole rim, and thereby insure 
equal and uniform action in all its parts. Some makers even 
gild the steel to prevent any danger of oxidation of the metal. 
The surface is then coated with powdered borax and water in 
the usual way, before being touched with the fingers, which is 
allowed to dry, the steel disc is then placed in a crucible, or in 
a heated mold of fire-clay or soapstone. In the former case, 



52 THE WATCH ADJUSTER' S MANUAL. 

enough of the best brass is put into the crucible to surround and 
cover the steel disc when melted, covered with powdered borax, 
and the whole is exposed to the fire in a suitable stove or 
furnace, till the brass melts and flows freely, then the whole is 
shaken or stirred with an iron rod to cause impurities to rise, 
and immediately removed and allowed to cool while the steel 
disc is forced to the bottom and held there with the rod till the 
brass begins to solidify. After the brass is well melted and the 
steel forced to the bottom, it is advisable to cool the crucible 
or mold rapidly, to prevent liquation, or the tendency of the 
different parts of the alloy to separate and produce a difference 
in the composition or texture of the metal in different portions 
of the mass, and also the tendency to crystallization in the in- 
terior during slow cooling. This is readily accomplished by 
setting the crucible on a cold stone slab or body of metal, which 
will rapidly conduct the heat away. In the latter case the 
brass is melted separately. As soon as it becomes thoroughly 
liquid and the characteristic greenish flame appears, it should 
be poured into the red-hot mold and the disc held down 
as before. The side of the disc which was cemented to the 
chuck should be down. The heat must not be too great, or 
blisters may arise and make the brass porous. Cool rapidly, as 
above directed. Old English watch movements are found to 
furnish brass which is generally very satisfactory. The melt- 
ing should be done by a charcoal or coke fire. The fumes from 
coal are very objectionable, especially from soft or bituminous 
coal, and ordinary wood is not much better, unless thoroughly 
seasoned and dry. When the brass is to be soldered on, a thin 
film of silver solder is interposed between the steel plate and 
brass ring when the latter is driven on, plenty of borax applied, 
and the whole is carefully exposed to heat till the solder flows 
satisfactorily. 

(113.) Shaping the balance. — When cold, the center-hole is 
cleaned out, the superfluous brass filed off the sides, and also on 
the edges till it is about three times the thickness it is to be when 
done, and afterwards turned down nearly to its final diameter; 
then the rim is carefully hammered to harden the brass without 
denting it or breaking the grain. This hammering should bring 
the rim to about the diameter it is to remain, so that as little 
as possible of the metal will have to be turned off, as that would 
remove more or less of the hardened surface and impair its 
value. The edges and outside of the rim are turned perfectly 
flat and true, and the inside of the steel plate is turned out in 
such a way as to leave the metal at the bottom of the cavity. 



THE WATCH ADJUSTER'S MANUAL. 53 

of the thickness the center-bar is desired to be, and the steel 
part of the rim about one-half the thickness which the brass 
portion outside will have when the balance is finished, and the 
cavity smoothed with emery powder. 

(114.) Finishing and drilling the rim. — It is then drilled and 
tapped for the screws, the number of which varies from twenty 
to thirty. American watches generally have thirteen holes on 
each half of the rim. Some makers locate the holes at a pro- 
gressively decreasing distance apart as they approach the free 
ends of the segments, — others make them an equal distance apart 
throughout. This is not material, but it is absolutel)' indispens- 
able that each opposite pair of screws be exactly in a diametri- 
cal line passing through the precise center of the balance. In- 
stead of screws, chronometer makers often use sliding weights, 
which may be moved along the rims and fastened at any desired 
point by a set-screw. But the use of screws for compensating 
is the rule for pocket watches. 

(115.) The bottom is next pierced and filed out, leaving the 
center-bar of exactly the same size and shape on each side of 
the center, and the rim of the same thickness from edge to edge, 
without filing or scratching the portion of it which was cut out 
in the lathe. The balance should now be carefully poised on 
an arbor, to see that the work has been equally and uniformly 
done, and then annealed by boiling in olive oil {6G) to remove 
internal strains produced by the working of the metal and bring 
the whole to a uniform molecular condition. This should be 
done before cutting. 

(116.) Cutting the rim. — The balance is then set up in the 
lathe again, and the rim polished. It is now cut, generally near 
the center-bar, so as to form two long sections or segments, but 
sometimes midway between the ends of the center-bar, thus 
forming four shorter segments. The drilling and cutting are 
best done by the help of a dividing engine, to insure exactness, 
and so that the two segments should be of precisely the same 
length, and shape of cut. It is necessary that all the opposite 
parts of the balance be of exactly the same thickness, shape 
and weight, as otherwise, even if the balance was in poise at 
the mean or middle temperature, it would not be so when the 
segments had changed their position under the influence of heat 
or cold, for their unequal motions would carry the compensating 
screws to different distances from the center, and render the 
rate utterly unreliable in different positions, or in carrying. It 
must also be staked or riveted concentrically upon the balance 
staff, as any fault here would vitiate all previous painstaking. 



54 THE WATCH ADJUSTER' S MANUAL. 

(117.) Where to cut the rifn. — Where the rim shall be cut is 
determined largely by the construction of the balance itself. 
Every maker tries to have a definite system, which he rigidly 
adheres to, and by this means he produces balances comparatively 
uniform, or at least having a certain character. The balances 
of some makers are more sensitive than those of others. The 
former do not need so long segments to produce the same effect. 
And each maker will by careful observation and experience find 
the length of segment which is suitable to his balances. Very 
long segments are apt to be irregular in extreme temperatures, 
while short ones may not have action enough to effect a com- 
pensation. If the rim is sufficiently sensitive, it may with ad- 
vantage be cut into four equal segments. But, in any case, 
when there are but two compensating segments, the cut should 
be far enough from the center-bar to afford a good hold upon 
the balance while handling it, without the fingers pressing on 
the free ends of the segments. The balance is cemented on a 
metal plate while cutting, to support and hold the rim. The plate 
is previously cut, with openings somewhat wider than the cuts 
will be in the rim. It is not cut radially, but obliquely, so 
that the end of the short segment laps a little over the adjacent 
end of the long one, protecting it from injury by rough handling. 

(118.) Making a spri?ig-steel balance. — By the ordinary method 
thus far described, the steel part of the rim is left soft. It has 
often been observed that the balance would be much more stable 
and uniform in its action, if the steel lamina could be left in the 
condition of a permanently elastic steel spring, as after being 
hardened and tempered. But thus far no acceptable way of 
reaching that result seems to have been found, and I therefore 
describe my way of producing a permanent spring-steel balance. 
It is made as before described, by the melting process, until the 
cavity is turned out, — except that the brass is left about three 
times the thickness it is to be when done. The arms or center- 
bar are cut out and the rim finished inside, as in section (113), 
but the rim is not drilled nor cut, although it is turned to its final 
width, i.e.^ from the top to the bottom. 

(119.) Stays for haj'denifig and tempering. — Turn up a disc of 
cast iron exactly fitting the inside of the rim, resting on the 
center-bar and reaching up exactly level with the steel edge of 
the rim. This is easily done, even in making a single balance. 
But in factories, where the sizes of all the parts are uniform, it 
would involve scarcely any expense, as the stays can be used 
continuously. On each side of the balance lay a cap, with its 
under, edge perfectly flat. One is in contact with the under 



THE WATCH ADJUSTER'S MANUAL. 



55 



surface of the rim and center-bar, the other with the rim and 
the disc, which in turn supports the inside of the rim and the 
top of the center-bar. The whole is screwed fast in a malleable 
iron clamp, and is ready to be heated in the cyanide bath, (62, 
73?) quenched in water, and tempered either in cyanide, (72, 
103,) or boiling oil, (66,) thus giving the steel rim the same 
temper as a hair spring. 

(120.) Figs. 6 and 7 show the balanced, the disc A^ the 
caps C, C, and clamp D. The disc can be made nearly as wide 
as the rim, and have a slot cut in one side to take in the center- 
bar, but it is not really necessary. For safety, a narrow strip 
of writing-paper can be laid on the center-bar, the disc over 
that, and the clamp screwed down hard to crush the paper and 





Fig. 6. 



Fig. 7. 



make perfect contact. Short conical points (screwed in) may 
project from the surface of the disc and sit into cavities in the 
caps, to hold the parts in proper position, after the manner of 
short, stubby steady pins. Or the caps can be turned out so as 
to sit down a little over the edge of the balance, as shown, for 
the same purpose. The caps may also have a central cavity 
for the screw of the clamp, to give central pressure. The clamp 
is wide, to expose all parts of the rim to equal heating and 
cooling. Or the caps can be held together in any other con- 
venient way. 

(i2T.) Finishing the balance. — Make a lathe chuck, 7^, to fit 
inside the rim snugly, with a shoulder sitting over the steel 
part, I, of the rim, but leaving the brass, 2, exposed. Pins, 4, 
rest against the edges of the center-bar, 3, to turn it by, or it is 
held and fastened on, in any convenient way. The brass may 
be compressed and hardened by bearing on it with a milling-tool 
with fine notches, and then turning off the notches, and repeat- 



56 THE WATCH ADJUSTER'S MANUAL, 

ing this till the brass is reduced nearly to its final thickness, 
then harden and compress with a smooth roller; or it can be 
turned down nearly to size, and then brought to size with the 
flat roller, or by cautiously hammering it evenly all round the 
rim. It is finally centered accurately in a lathe, the rough 
edges turned off, and the outside turned perfectly true and to 
size. Then poise, anneal in oil as described for ordinary bal- 
ances, except that I prefer to leave these balances as hard as is 
safe, (say, not draw the steel below a straw color,) because hard 
steel is much less liable to be magnetized than that which is 
carried to a lower temper. Then cut the rim, as before. 

(122.) Rounding a balance. — When the rim is cut apart, the 
segments fly "out of round," and require to be trued up. This 
is always done by hand, by very gradual and gentle curves, and 
is a somewhat tedious operation. In trueing a balance, whether 
new or one that has been bent, use no pliers or other tools to 
bend it into shape, but spring it very carefully with the fingers. 
If a rather sharp bend is wanted at any particular point, place 
the thumb or finger-nails at that point as a support, and spring 
the segment on each side, against the nail. The novice must 
use the utmost care, or he will bend it too much, or in some 
screw-hole, and will be very likely to crack it, when it will be 
ruined, beyond the power of the cleverest workman to remedy. 
At first he had better practice only on abandoned balances, till 
he has acquired a little skill and experience. 

This finishes the work of the balance maker. Further in- 
structions for trueing and poising are given in the next chapter. 

(123.) Making non-magnetic balances. — There are several varie- 
ties of non-magnetic balances now in use. For a plain balance, 
gold, brass, aluminum, bronze, or any metal except iron, steel, 
or nickel can be employed. For compensating balances, the 
most promising construction yet tried is that with the Paillard 
alloys of palladium. In some, the inner lamina is of the palla- 
dium alloy and the outer one of brass; in others, the outer 
lamina is made from a palladium alloy having a rate of expan- 
sion for heat different from that of the inner one. Other 
makers also use palladium alloys. (Alloys of platinum and 
other metals have also been tried.) The compositions of tlie 
various alloys used, and the methods of making and working 
them, are not made known, but the palladium balances can be 
bought ready-made, by those who wish to use them. 



THE WATCH ADJUSTER' S MANUAL. 57 

CHAPTER X. 
Selecting and Testing Watch Balances. 

(124.) The balance is the governor. — The balance is the gov- 
ernor or regulator of the time-keeping mechanism. Upon it 
depends the possibility of the watch keeping time. If its size 
and weight are not correctly proportioned to the motive force 
and the movement generally, no adjustment or combination of 
the balance spring and other parts can make the watch a good 
timepiece. The spring is always secondary to the balance, and 
by many makers the construction of the entire movement is 
required to conform to the weight and proportions of the stan- 
dard balance. In other cases, the particular construction 
adopted for the balance is determined by careful tests of the 
performances of different balances with a standard type of 
movement. 

(125.) Effects of improper size and weight. — If a balance is too 
heavy, there is more variation in the different positions; espe- 
cially if the pivots have been made larger on account of its 
weight; if much too heavy, it will be impossible to time it in 
positions. A heavy balance, with slow vibrations, is more af- 
fected by all resistances and frictions which oppose its motion, 
jarring, shaking, etc. When the motive force is too great rela- 
tively to the balance, the watch will gain in the horizontal and 
lose in the vertical positions. If the balance is too light it will 
be too sensitive to variations in the motive force, although, if it 
is both light and large, there will be little friction on the pivots, 
and little variation between the horizontal and hanging posi- 
tions. If heavy and also too small, there is excessive friction 
at the pivots and variation in positions, but it is less affected by 
external disturbing influences. 

(126.) Calculati7ig the proper size for balance. — In calculations 
of the size of the balance, the diameter is not necessarily the 
external diameter as measured. Supposing all the weight of 
the balance to be concentrated in a sphere or ball at each end 
of a center-bar without any weight, the distance from the center 
of the balance to the center of the sphere would be the radius 
of gyration^ and the distance between the centers of the two 
spheres would be tht geometrical diatneter^ or diameter of gyration 
of the balance. In a plain balance or one with few and light 
screws, the center of weight would come about at the center of 
the rim, or a little inside of that. In compensation balances, 



58 THE WATCH ADJUSTER' S MANUAL. 

with numerous and heavy screws, the radius of gyration is gen- 
erally taken as the distance from the center of the axis to the 
outer edge of the rim. 

(127.) The 7noment of t?iertia of a balance is its resistance to 
a change of velocity, or, commonly speaking, its controlling 
power, — and is calculated by the formula: 

A=WXr\ (i) 

where A is the moment of inertia; W, the weight of the bal- 
ance; and r is the radius of gyration. This means that the 
controlling power of the balance increases in proportion to its 
weight, and also in proportion to the square of its radius of gyra- 
tion, i.e., of its semi-diameter measured as stated in section 
(126) above. 

(128.) The period of vibration, of a balance with a spring at- 
tached, is usually calculated by the following formula: 



-^|/: 



^^ (?) 



where 7" is the period of a single vibration in seconds; A is the 
moment of inertia of the balance; L is the acting length of the 
hairspring; M, the moment of elasticity of the spring; and tt is 
equal to 3. 14159. 

(129.) Example. — The actual calculation of the period of vi- 
bration by this formula is rather difficult and tedious, but for 
purposes of mere co?nparison of different balances, the operation 
can be greatly simplified and shortened. If we wish to compare 
any two balances, one of which may be correct and the other 
different from it, we distinguish the symbols referring to them 
by the figures i and 2, written after them and below the line; 
thus, T^ would mean the period of the first or standard balance, 
whose proportions and performance we know, and T^ would in- 
dicate that of the second or trial balance, which we are study- 
ing or testing; W^ and W^ would be their respective weights, 
A^ and A^ their moments of inertia, and r^ and r, their radii of 
gyration. In comparing two balances, we have this proportion: 



r, : T :: iza/'LAIi : n i/d^^. (3) 

(130.) Simplifying the formula. — In this proportion, the sym- 
bols L and M refer to the spring, and as they and the symbol it 
are not changed in our consideration or comparison of different 
balances, and as they are found in both the third and fourth 



THE WATCH ADJUSTER' S MANUAL. 59 

numbers of the proportion, we can omit them from the propor- 
tion without affecting its truth. Doing so, our proportion be- 
comes: 



\: T,:: |/^, : \/a,, (4) 



which means that the periods of vibration of the two balances 
will be in proportion to the square roots of their moments of 
inertia. As A equals W X ^j, (127,) we substitute that for A 
in the proportion, and it then becomes: — 



r, : r, :: \/ W, X r^ : ^ W, X r^. (5) 

We have now eliminated everything which does not relate to the 
balance. 

(131.) Calculating the number of vibrations. — But it is much 
easier for most workmen to think of the number of vibrations 
in a given time, say, one minute, than of the period or duration 
of a vibration. For instance, in an 18,000 train, the period of 
the vibration, 7", would be \ second, while the number of vibra- 
tions per minute, F, would be 300. It is also plain that as the 
period T becomes greater, the number F becomes smaller, and 
in order to make a proportion expressing their ratios, we must 
reverse the order in which they are written, thus: 

7-, : T, :: V, : V,; ox T, : r, :: K, : V,. (6) 

Both expressions are true; and if we take the latter, and substi- 
tute the equivalents of T for that symbol in formula (5), we 
have the proportion: 

K, : V,:: \/ W, x r,' : \/ W^ X r,'. (7) 

In order to get rid of the square roots, we will square all four 
members of the proportion, which will not affect its truth, and 
it then becomes: 

V^' : F; :: W^ X r^' : W^ X ^^ (8) 

(132.) Calculating the vibrations for balances of different weights. 
— If we wish to compare two balances attached to the same hair 
springy and having the same radii of gyration but differing in 
weight, we can omit the symbol r in the above formula, because 
it would be the same in both the third and the fourth members; 
and the proportion would then be: 

V; : V; : : W,: W, (9) 



6o THE WATCH ADJUSTER' S MANUAL. 

which means that the squares of the numbers of vibrations of 
the two balances will be inversely proportional to their weights, 
expressed either in grammes or grains — which is not at all diffi- 
cult to work out. 

(133.) Calc7(latifjg the vibrations for balances of different sizes. — 
On the other hand, if the balances have the same weight, but 
different geometrical diameter (126,) i.e.^ have different radii 
of gyration, we can drop the symbol W from the third and 
fourth members of formula (8), and we would then get the pro- 
portion: 

F,' : F; :: r/ : r/. (lo) 

It will be observed that all four members of this formula are 
squared. To save some trouble in calculating, we will take the 
square roots of all four members, which will not affect the truth 
of the proportion, and we have: 

V^. V, :: r, : r„ (ii) 

which means that the vibrations of the two balances will be in 
inverse proportion to their radii of gyration, i.e.^ the number of 
vibrations will become less in proportion as the size of the bal- 
ance becomes greater. 

(134.) Observations. — Formulas (9) and (11) are good work- 
ing proportions, by which any one can easily make all necessary 
calculations. I have taken considerable trouble to explain fully 
how we have arrived at them, step by step, and their meanings, 
so that even those who have no mathematical training can 
understand them and how to use them. 

(135.) Calculating the number of minutes per hour. — In these 
calculations, instead of the number of vibrations per minute, 
we can take the number of minutes passed over by the watch 
hands in an hour, or 60 minutes. Thus, if one watch or bal- 
ance went correctly, while the other lost 5 minutes in an hour, 
the proportion would be 60: 55. If the second watch or balance 
gained 5 minutes in an hour, the numerical value of V^-. V^ 
would of course be in the ratio of 60 to 65. 

(136.) Method of using the for7?iulas. — In making calculations 
by these formulas put iht fgures representing the different letters 
in place of the letters, so far as known. Calculation will then 
give you the value of the letter whose value you seek. Instead 
of the radius (semi-diameter) of gyration, it will be the same 
thing to take the diameter of gyration, or the geometrical 
diameter, measured as in section (126). Multiply the first and 
fourth numbers together, and the second and third together; 



THE WATCH ADJUSTER' S MANUAL, 6i 

the two products will be equal. Then get the unknown symbol 
on one side of the equation, and all the figures on the other 
side, and they will give the value of the symbol or letter. 

(137.) Example. — Suppose a balance weighing six penny- 
weights runs 10 minutes slow in an hour, what must be the 
weight of a similar balance to run correctly? Substituting the 
above values for V and W in formula 9, and squaring the num- 
bers or values of F, we have: 

2500 : 3600 :: W^ : 6, 

/.<?., the square of the number of minutes (50) given per hour 
by the first balance, is to the square of the correct number (60) 
per hour, as the weight of the second balance (unknown) is to 
the weight of the first balance (6), which, after multiplying, 
gives us the equation 

3600 X IV^ = 15,000, or IV^ — 4.166, 
or 4\ pennyweights. By using the number of grains the first 
balance weighs, you will get the weight of the second balance 
in grains. 

(138.) Suppose a balance of a certain weight having a diame- 
ter (of gyration) of .648 inch, gives 380 vibrations per minute, 
what must be the geometrical diameter of a similar balance, of 
the same weight, to give 300 vibrations per minute ? Accord- 
ing to formula (n), 

380 : 300 :: r^ : .648, 

which on multiplying gives 300 X ^^=- 246.240, or r^^^.Szi inch 
— a trifle over y^^^ inch in diameter. 

These examples will show how to ascertain the value of any 
member of the proportion, when the values of the other three 
members are known. Care must be taken to observe the proper 
order of the symbols, as shown by the figure under each one in 
the formulas. 

(139.) Empirical rules for size of balance. — The foregoing cal- 
culations arrive at the proper size and weight for the balance 
by a process of coinparisoji with some other balance which has 
been tested, so that both its performance and its weight and 
dimensions are known. That is the ultimate recourse of the 
manufacturer. He tries to learn the best proportions from all 
previous experience — both of his own and of others. Having 
found the proportions which give the best performance, he 
adopts that balance as his standard of comparison. But in or- 
dinary practice, much shorter methods are followed. One rule 
is that the diameter of the balance should be the same as that 
of the cover of the mainspring barrel. Others say, for a ^ 



62 THE WATCH ADJUSTER' S MANUAL, 

plate watch, it should equal the inside diameter of the barrel. 
Another rule is, that it should be half the diameter of the upper 
or potance plate of the watch. Others say that it should be 
from 2 to 2^ times the diameter of the escape wheel, or be 5 
times the width of the mainspring. But these methods evidently 
can only secure a more or less close approximation to correct- 
ness, leaving the further corrections to be made either by cal- 
culation, as already described, or by the tests of performance 
given in sections (141, 142). 

(140.) Following good models. — But it should be remembered 
that the best performance is obtained only when there is a cer- 
tain proportion between the size and weight of the balance and 
the number of vibrations it makes. That is to say, a balance 
which would perform well at 18,000 vibrations per hour might 
be very unreliable at 16,200 or 20,000 vibrations, even if the 
motive force and the hair spring were modified correspondingly. 
There is no better guide, therefore, than a similar movement 
which is known to perform well. And copying it is not mere 
slavish imitation, but a wise profiting by experience. 

(141.) Testing the balance for weight and size. — After the bal- 
ance is in the watch, it can be tested as follows: — Block the 
train with a bristle, so that the balance is perfectly free from the 
motive force or other influence, and stands in its central position 
or at the point of rest. Now mark on the plate, with a speck of 
rouge or whiting in oil, the position of the banking pin, or of 
the cut in the rim, or of some prominent screw or other mark, 
by which you can easily and surely note the extent of the bal- 
ance vibrations. Then start the watch, and when the balance 
has acquired its normal or regular arc, mark the point attained 
by the banking pin, etc. This mark indicates the full arc of 
vibration. Now gently stop the balance and bring the pin 
to its central position, then let it start to running, and count 
the number of vibrations it requires for reaching its full arc. 
Watch the banking pin with the eye-glass, and repeat the test 
if necessary. 

(142.) Indications of this test. — If the balance is too light, it 
will acquire its full arc almost immediately; if too heavy, it may 
require 15 or 18 vibrations to do so. These indications refer 
to the proper or improper weight of the balance. To test the 
size^ after the balance has acquired its full arc, gently increase 
the strength of the motive force, (by pressing against the arm 
of the center wheel, or in some similar way,) and if the balance 
is very sensitive to the change, it is generally too small; if the 
vibrations are hardly any affected by the pressure, it is too 



THE WATCH ADJUSTER' S MANUAL. 63 

large. This test (of size) evidently applies mainly to the lever 
and chronometer, since the frictional escapements are self-com- 
pensating for changes in the motive force. By making such 
tests for both size and weight on all perfect watches that pass 
through his hands, he will have a standard of behavior for each 
kind of watch, which will enable him to quickly detect any which 
vary from the correct proportions. 

In box chronometers, there is not the same objection to heavy 
balances as there is in watches, because the former are al- 
ways kept in one position. A heavier balance with slow vibra- 
tions can therefore be used, and its greater momentum secures 
a steadier rate than a lighter balance would give. 

(143.) Selecting competisation balances. — The foregoing remarks 
apply to any kind of balance, having reference merely to the 
size and weight. In selecting a compensating balance, it must 
also be of such construction as to respond to variations in the 
temperature promptly, i.e.., at least as quickly as the hair spring, 
(259,) and to act sufficiently to compensate for those variations. 
A thin rim is more sensitive to changes of temperature than a 
thicker one, but it must be thick enough to hold its shape while 
vibrating and not allow the screws to fly outwards by centrifugal 
force. As to the sufficiency of the compensation, that can only 
be told by actual trial in different temperatures. 

(144.) JExpansion balances. — All balances having a rim com- 
posed of two metals, made and cut as before described, are 
technically called expansion balances. They may be well made 
and capable of compensating if adjusted, in which case they 
can properly be termed compensation or chronometer balances 
— the former being the correct title. Or they may be merely 
imitations of compensation balances, incapable of compensating. 
This generally can be told only by trial — unless there is some 
glaring mechanical imperfection which shows that they cannot 
compensate. 

(145.) Distinguishing ^''adjusted'' balances. — No one can tell by 
mere inspection when a balance is adjusted, for there is abso- 
lutely no difference in appearance between one adjusted and one 
not adjusted. One may be as near perfect as the highest skill 
and many efforts can get it, while the other may be " wild." but 
no one can distinguish them by their looks — only by trial in 
the watch. So of the balances sold by material dealers, — they 
may be from an excellent maker, made with every care, and all 
apparently equally good in every respect. Yet a trial will show 
that no two will act just alike. While some will be good, others 
may be worthless for accurate performance. The only way to 



64 THE WATCH ADJUSTER' S MANUAL. 

ascertain is to test their running in heat and cold. It may be 
said, however, that the thinner and higher the rim the stronger 
the compensating action will be. These remarks of course refer 
only to balances completed and cut as already described. 

(146.) hnitation expansio?i balajices. — Very many watches are 
provided with balances having rims of steel and brass, with 
screws inserted, the same as before stated, except that the rims 
are not cut, or are cut only partly through, w^hich amounts to 
the same thing. These may be in fact expansion or compensa- 
tion balances, but the laiJiinc^ or compensating segments cannot 
compensate, because they are not allowed to act. Any balance 
the rim of which is not cut entirely through, is certainly not 
"adjusted," although it may be called a compensation balance. 
It is no better than the common balances of one metal, with 
screws in their rims, which are only imitations of chronometer 
balances. Such balances, however, are better than plain ones, 
in that they may be timed by these screws, either turning them 
in or out, or putting in lighter or heavier screws, to suit the 
strength of the hair spring. They are also safer from injury 
while being handled by bungling workmen, and add something 
to the appearance of the movement, which is all that many 
people judge by. They are good enough for customers who do 
not comprehend the value of a real compensation balance, and 
are unwilling to pay the additional price, — and consequently 
they cannot expect anything better than an imitation balance. 



CHAPTER XL 
Correcting and Finishing Balances. 

(147.) General correction of balances. — There are various ma- 
nipulations and corrections needed by balances, which are not 
connected with the adjustment for temperatures, and all such 
faults will be treated in this chapter, whether they relate to the 
balance before it is fitted in the watch, or before or after the 
compensation adjustment. 

(148.) Eccentric balance. — The defect which is easiest to de- 
tect, even before the balance is fitted in the watch, is eccentric- 
ity, in which case the hole is not exactly central with the rim at 
the ends of the center-bar. The hole could of course be changed 
and made central, if that was all. But the existence of such a 
fault shows that the maker has not observed the most important 
principles of balance making, and in all probability the entire 



THE WATCH ADJUSTER' S MANUAL. 65 

balance is made with equal disregard of proper methods, and 
the safest plan is to reject it. To test a loose balance, mount 
it on a perfectly true arbor, and try it in the calipers, or even 
in the turns, with sufficient pressure on the points of the arbor 
to hold it in any position it may be placed in. Then set the 
slip-piece of the calipers (or the lathe rest) to barely escape 
touching the outer edge of the rim with its sharp corner. 
With a strong magnifying glass, see if the rim is concentric 
with the hole while the balance is turned around. If so, 
the outside of the rim, at each end of the center-bar, will be 
equally distant from the center, or will touch the slip-piece or 
the rest, alike. If not, perfect action cannot be expected, for 
it is evident that the two segments have different centers of 
motion from which to act in either direction under change of 
temperature. Then test the inner edge of the rim in the same 
way. 

(149,) Testing a balance on the staff. — If it is already on the 
staff, test it as before described, and if found to be eccentric at 
the ends of the center bar, drive it off the staff and test again. 
If the error is in the balance reject it; but if the balance is 
concentric in itself, and the fault is in the staff, the quickest and 
best remedy is, probably, to turn the staff down a little smaller, 
so that the balance will go on somewhat loosely, then, by rivet- 
ing it a little harder on one side than the other, throw the bal- 
ance a little further out on that side, and make the rim concen- 
tric. If the balance hole was already too large for the staff, 
and that was the cause of the eccentricity, re-staking properly 
will bring it concentric with the pivots. Or if the arbor of the 
staff was not concentric with the pivots, it should be made so 
in the lathe, and the balance then riveted concentrically upon 
it. Never attempt to bend the arms of the center-bar, except 
to straighten or level them after some botch has bent them out 
of shape; such a balance is of little value for accurate perfor- 
mance. 

(150.) Trueitig up the balance. — If the balance is concentric at 
the ends of the center-bar, but not at other places on the rim, 
it must be trued up at mean temperature. Avoid touching the 
balance with the fingers or otherwise warming it, while testing 
it, but turn it slowly with a stick of pegwood, and note where 
the rim begins to go in or out from the true circle indicated 
by the sharp corner of the slip-piece or rest. Have ready a 
little whiting and oil, mixed, and mark the rim with a speck of 
this, on the outside where it begins to go out, on the inside 
where it begins to go inward. So go around the whole rim, 
5 



66 THE WATCH ADJUSTER'S MANUAL. 

marking every such place, and you will have a clear idea of the 
condition of the balance. In trueing, take one segment at a 
time, begin at the center-bar and work from there to the end of 
the segment, testing it after every alteration before making 
another, till it is true to the end. Then true the other seg- 
ment in the same way. All this should be done at the middle 
temperature for which the balance is to be adjusted. If the 
extremes are to be 30° and 120°, the mean will be 75°, at which 
temperature the balance should be caused to be round or con- 
centric. If the extremes are 55° and 95°, the mean will be 
65°. The temperature of the adjustment-room should be kept 
nearly at that degree, and if the heat of the sun, stove, lamp, 
fingers or breath, should warm the balance above that, it should 
be cooled in a dish of alcohol before testing the roundness in 
the calipers, as the balance will not be round when it is either 
warmer or colder than that temperature. Should there be 
jewels on the staff which are fastened in with shellac, the al- 
cohol would loosen them, and benzine or ether should be used 
instead. 

(151.) Tempering or setting the balance. — After rounding the 
balance, it is then heated on a metal plate to about 212° Fahr. , 
and, when cooled to the above temperature, if not round, it is 
rounded again as before. This heating and rounding are re- 
peated if necessary. The object is to temper the balance, and 
free it from the tension or strain which the bending process 
produces in the metals. Otherwise, it would be very likely to 
change its form gradually, while running, and derange the rate. 
If the balance is new, and has been hammered too much in 
making, or not heated enough afterwards, the rim will probably 
curve inwards and " set" in that shape, causing a gain in time. 
Or, if not hammered enough, or heated too much, it will spring 
outward and lose time. In warm weather, merely handling the 
balance with the bare fingers is liable to cause the segments to 
" set" differently. They should therefore be handled as little 
as possible. See that the rim is true in *' the flat," as well as 
in "the round," which should always be tried with the balance 
in the vertical position, or edge upwards, so that the segments 
may assume their natural position as regards flatness. 

(152.) Poising the balance. — Then poise it accurately, (292,) 
with the screws turned clear in, but not tight. If they were 
screwed in tightly, the pressure of their heads against the rim 
would affect its curvature while the brass part of it was ex- 
panded under the influence of heat, and might even cause a 
change of shape in the rim, which, from the method of its pro- 



THE WATCH ADJUSTER'S MANUAL. 67 

duction, is comparatively soft. The above directions apply 
only to new balances. We often find balances in use having 
their screws all considerably turned out to make the rate 
slower. In that case we must let them remain so, if the rate 
is correct and the opposite screws are at equal distances from 
the center, as turning them in might necessitate the fitting of a 
new hair spring. But if we have orders to make everything 
perfect^ and as it should be, we ought to turn the screws home, 
as directed above, then fit a hair spring which will give correct 
time, — provided the balance is of the right size and weight for 
the movement. If not, it should be entirely discarded, and a 
new one put in. Also now test the balance for magnetism, 
(30, 34, 37,) if it has not been done before. 

(153.) In-egular action. — Whenever a balance shows any 
irregularity in time, it should be tested as to its poise in extreme 
temperatures^ say 35° and 120° Fahrenheit. And it is well to 
test the balances of all fine movements before beginning the- 
compensation — also all new balances. Sometimes the brass and 
steel are not firmly united, and will separate more or less under 
change of temperature. This defect may not be so great as to- 
be discoverable by prying the metals apart, and yet cause the 
two segments to operate very irregularly and differently. 
Sometimes the rim is very slightly "out of round," or not truly 
circular, when the segments will spring in or out differently, 
from their different shape or curvature. Sometimes one seg- 
ment has been bent accidentally and trued up again, or for 
some other reason one segment has been bent back and forth 
more than the other, and as this bending impairs the elasticity 
and changes the condition of the metals, its action will be differ- 
ent from that of the other segment. It is of the highest impor- 
tance to handle a compensation balance with the utmost care, 
to avoid the slightest springing or straining of the segments. 
Flaws or defects in the metal or workmanship of the balance 
will also cause a difference of action in the segments. If one 
side has been bruised or dented in the hammering process, that 
side will show the effects ever after. Care should also be taken 
not to expose a balance to a heat much exceeding 130° to 140° 
in waxing it on the lathe, or for any other purpose, and not for 
any length of time to that temperature, as it is liable to cause 
the segments to " set" more or less differently from their former 
shape. 

(154.) Poising in extremes may be done by placing the balance 
on a hot or cold metal plate, to bring it to the desired temper- 
ature, and then laying it on the straight-edge poising tool. If 



68 THE WATCH ADJUSTER'S MANUAL. 

it changes its position, and comes to rest each time with a cer- 
tain side up, the segment found down in cold, or up in heat, 
has acted more strongly than the other, and both should be 
closely examined. If its position has remained unchanged it 
may be inferred that the error is very small, if any exists. But 
if one side is repeatedly found down, either in heat or cold, the 
fault must be traced out and corrected before going further. 

(155.) Faults in compensation or expansion balances. — Among 
the faults which concern the expansion balance, the following 
may be mentioned : 

1. Centrifugal force may throw the two segments out un- 
equally while vibrating, and throw it out of poise. 

2. Ditto; this maybe different in the long and short arcs, 
and produce effects wrongly attributed to lack of isochronism 
in the spring. 

3. The balance segments may be too thin, or the screws too 
heavy for it, and whenever the vibrations become unusually 
large by jarring, etc., the screws may hit something near them 
and ruin the regularity of the timing. A good way to detect 
the above faults is to arrange a circular arc of metal close to 
the exterior of the balance, but giving all the clearance that it 
should have. Then if it hit this arc when set going, its motion 
would be visibly affected, and perhaps audibly. Or a little 
whiting and oil could be put on the nearest point, and if the 
screws come out too far they will receive a white mark. 

4. The pivots may not be round, or the balance not riveted 
concentrically on the staff, (or pivot bent,) causing it to be out 
of poise, and affecting the rate in heat and cold, also the time 
in different positions, and the isochronism. 

5. The two segments may not expand and contract alike in 
heat and cold, carrying the screws to unequal distances from 
the center, producing errors in the poise, compensation and 
isochronism. 

6. The segments (or one of them) may have been bent out 
of the true circular form. 

7. A segment may have been bent, and restored to shape, 
causing a weakening of the rim at that point, with irregular 
action. 

8. Other similar faults might be mentioned. All of them will 
produce different effects when the watch is held in different 
positions — according to whether the heavier side is then at the 
top, bottom, or one side of the balance center. 

(156.) Faults of tmcut or plain balances. — I will only mention 
-the -following: i. When a bi-metallic rim it not cut through, the 



THE WATCH ADJUSTER'S MANUAL. 69 

expansion of the brass of the outside, in heat, causes the rim 
between the arms or ends of the center-bar to bulge outward 
into an oval form; in cold, the rim is forced inward; the differ- 
ent parts may also act or yield unequally, and the balance 
be put out of poise, or spring the arms as well as the rim out of 
shape. All such balances should have two cuts entirely through 
the brass, between the arms, /.<?., in a three-armed balance, 
there would be six cuts. But it is much better to use balances 
of one metal, carrying screws to give the desired weight. 
2. Test for magnetism. See Chapter III. 



PART FOURTH. 
SPRINGING AND TIMING, 



CHAPTER XII. 

Conveniences for Timing. The Regulator or Stand- 
ard Clock. 

(157.) The regulator may be of any variety, provided its rate 
is constant. The mercurial and the gridiron pendulums are 
both good, and even wood pendulum rods have done excellent 
service. All depends on the maker. A good maker can make 
either kind of clock do first-class service. Of course, each rec- 
ommends his kind as the best, but the only safe way to buy is 
to have a guarantee stating what it ivill do. Get as good a one 
as you can afford, but always insist that its rate shall be regu- 
lar, and shall be known. If its rate is not known, it has never 
been regulated, and you will have to take your chances with it. 

(158,) For ti??iing purposes a regulator beating seconds is the 
most convenient; but one beating half-seconds is nearly as 
good, provided it is accurate. But a clock which beats any- 
thing except seconds or half-seconds is worthless for timing. 
It should be compared with some correct time at least as often 
as every week or ten days, no matter how good its quality or 
how closely it has been rated. Something may happen at any 
time to cause an error in running, and perhaps a large error. 
If you are not watching the clock, you would not know it, but it 
would be disarranging all your watches to suit the clock. Be- 
sides the trouble you would make in extra work, there would be 
the loss of reputation and the dissatisfaction of customers, — and 
if your rival across the street should notice it, you would never 
hear the last of it. Watch your clock. 

(159.) Getting correct time. — Your best way is to get it by 
telegraph. In most parts of the country, the time is tele- 
graphed from some observatory, or from the headquarters of 
the telegraph company, at a certain hour, for watchmakers and 
others on the line. You can ascertain this by inquiring at your 



THE WATCH ADJUSTER'S MANUAL. 71 

telegraph office. If not, the railroad company may send cor- 
rect time over the road for its own offices and employees — and 
very likely they would like to have your assistance in taking it 
off the wire and setting their clocks and watches. In writing 
down the time, one dash after the figures means minutes, two 
dashes mean seconds. 

The signals are sent over the wire in the following manner. 
At 11-56-45" A.M., i.e.^ 3-15" before noon, all commercial 
business over the line is stopped, and the time-transmitting ap- 
paratus at Washington is switched into the line circuit. The 
transmitting clock has just been compared with the standard 
clock of the Naval Observatory and set exactly with it. On 
the seconds-hand pinion arbor of the transmitting clock is a 
special wheel of 60 teeth, each tooth of which sends a signal 
over the line indicating the seconds — each signal being heard 
at the telegraph offices as a click of the telegraph instruments. 
The 29th tooth of this wheel is omitted, also, the 55th to 59th, 
both inclusive. Consequently, no signals are sent for the 
seconds bearing those numbers, but the telegraph instrument 
gives a click for all the other seconds, during each minute, 
until noon. 

When the first click is heard, therefore, you know that the 
correct time is 11-56-45" a.m., i.e.^ 56 minutes and 45 seconds 
past II o'clock. The clicks then continue each second till the 
55th, which is omitted; the instrument is then still during the 
remainder of the minute. At exactly 11-57-0" the clicks begin 
again, continuing each second till the 29th, which is omitted. 
At 11-57-30" they begin again, continuing till the 55th second 
— and so on, as above described. You thus get signals indicat- 
ing the minute and half-minute, after a warning silence each 
time, 7 times, or 4 minutes in succession. This gives you the 
opportunity to compare your watch 7 times, or to set it and 
compare again, if you wish. Although it does not affect the 
result in any way, I would observe that the signals are sent a 
little differently from the others, in the last minute, as the 
clicks stop at the 50th second, instead of the 55th as in the 
other minutes. This is to give time for switching in the appar- 
atus for dropping the time-balls, which is done by the signal 
sent at exactly 12 o'clock, noon. The foregoing is the United 
States government system for sending out Naval Observatory 
time, and it is also followed by most of the other Observatories 
throughout the country. The government sends such signals 
daily, but in some localities they are only sent on a certain day 
or days of the week. The signals sent by the government give 



72 THE WATCH ADJUSTER'S MANUAL. 

mean time for the 75th meridian, or meridian of Washington, 
D. C. In other parts of the country different meridians may 
be meant. If so, you will find which it is by inquiry at the tel- 
egraph office. 

(160.) Taking ti?ne off the wire, by a watch. — Take with you a 
watch whose seconds dial is evenly divided off, and preferably 
with a large circle and a long hand. It should have been ac- 
curately set by the regulator before starting. Seat yourself where 
you can hear the ticking of the telegraph instrument clearly, 
and also have a good light on the dial. Arrange a card, slip of 
paper, or even a finger-nail, on the glass so that you can keep 
the edge of it close to the point of the hand, i.e., if the hand is 
after the 60, you draw the card back so as to keep the hand 
just visible until the " time tick," then hold the card still and 
count the number of seconds to the 60. If the hand is before 
the 60, you follow it up with the edge of the card till the time 
tick, then hold it still and count up the seconds as before. 
Then observe how many minutes (if any) the minute-hand is 
ahead or behind 12 o'clock — or the hour of sending the time. 
Make a memorandum of the variation, to avoid any possi- 
bility of error or forgetting. Thus, if the time on your watch 
was i2h, o', 13", you were 13 seconds fast; but if the time was 
iih, 59', 13", you were 47 seconds slow. In the same way, 
compare your watch with the other signals, before noon. For 
the method of getting time to fractions of seconds, see sections 
(206 to 208). By this method you count the beats or jumps 
of the seconds hand. 

(161.) Another way, by chronograph, is by means of an inde- 
pendent center-seconds watch. A chronograph, or a split-sec- 
onds watch, which is a double chronograph, is preferable, as it 
admits of observing the fractions of seconds. Two observa- 
tions are taken, one at the time tick, the other when your watch 
reaches the hour of signaling. If your watch is slow, you press 
the push once, at the time tick, to start the chronograph 
hand from the 60. You press it again when the seconds-hand 
of your watch reaches its 60 at exactly 12 o'clock, to stop the 
chronograph hand. The number of seconds it stands after the 
60 shows how many seconds you are slow. If your watch is 
fast, you start the hand at exactly 12 o'clock by the watch, and 
stop it at the time tick. When you use a split-seconds, you 
start it shortly before the first push, and stop one hand at 12 
o'clock on your watch, and the other at the time tick as before, 
and compare the two hands. Supposing the watch to have 
been set by the regulator when starting, you can see when you 



THE WATCH ADJUSTER'S MANUAL. 73 

get back whether it is still exactly with it, which gives you a 
check upon the correctness of your observation, that you would 
not have if your watch had not been set beforehand — for you 
now know that your chronograph is all right, and can safely 
make the proper change in your regulator. See (159). 

(162.) Getting correct time by observations of the stars, or of the 
sun, may be done when telegraphic time is not available. It 
would take too much space to explain the use of the transits, 
quadrants, sextants, dipleidoscopes or other instruments em- 
ployed, the different kinds of time, and the necessary calcula- 
tions and corrections to be made, and the reader is referred to 
special treatises on that subject. The most popular and prac- 
tical work in this line is that of Latimer Clark, which can be 
obtained from the publishers of scientific books, or of any of the 
trade journals. 

(^v^Z-^ Changing the regulator. — If the error is small, make a 
note of it on the record, (for you should keep a rate sheet for 
the clock, as well as for watches,) and wait. If the error is the 
same, or about the same, the next time — or, at least, is in the 
same direction, you can safely make the proper correction. 
But when you have got it as close as you can, it is better not 
to change it for any slight error, but note the rate and let it go. 
Possibly something will affect it a hair the other way next time, 
and remove the error last noted. Even if it does not, it is bet- 
ter to have a slight error, and know what it is^ than to be always 
changing the clock and not know whether it is going fast or 
slow. If you know the error you can keep a card with the 
amount marked on it for every day, and consult that when 
making the final adjustments of your watches, or comparing 
customers' fine watches. 

(164.) Setting the regulator. — Never set the seconds-hand 
back, nor do anything to the other hands, or to the wheels, 
which would cause the escape wheel to turn backwards, as it 
would smear the oil from the backs of the escape-wheel teeth 
over the pallets, and probably change the rate of the clock. 
If the regulator is too fast, stop the pendulum, and start it 
again at the proper time, or you can put a weight on the pen- 
dulum to make it lose rapidly till the error is corrected, then 
remove the weight. If the clock is slow, the hands can be 
moved forward; they should not turn too hard, or there is risk 
of changing or injuring the escapement. 

When the clock is but a few seconds, or a fraction of a sec- 
ond slow, (or fast,) it can be set to time by the pendulum. 
The method followed at the United States Naval Observatory, 



74 



THE WATCH ADJUSTER'S MANUAL. 



and many others, is to cause it to vibrate a little more rapidly 
or slowly, as required. If it is only a small fraction of a second 
out of the way, merely touching it gently with the finger will 
be sufficient, either retarding its forward motion, or accelerat- 
ing it. In the latter case, care must be taken not to make it 
swing too far. If the clock is much too slow, take hold of 
each side and vibrate the pendulum more rapidly than usual, 
till the loss is corrected — moving it far enough to escape and 
"tick," but no further, else the oil may be displaced and the 
rate changed. 

(165.) The dial. — The construction and perfection of the 
movement and the pendulum are points settled when you pur- 
chased the clock. But there are other points, which concern 
the timing, and are still under your control, and we will note 
a few which should be looked after. The dial must of course 
be evenly divided off — especially the circle of the seconds-hand. 
It must be so fastened to the movement that the arbors or 
pivots carrying the hands will stand exactly in the center of 
the dial holes, and the holes must be exactly in the centre 0/ the 
circles. Test these points, for they are important in a fine 
clock — and these directions refer to fine clocks. If the sec- 
onds-hand pivot, for instance, is above the center of its 





circle, shown in Fig. 8, at de, the hand will be too slow at 15 
seconds and too fast at the 45 mark. In the same way, if the 
pivot stands to the left of the center, as in Fig. 9, so that the 
point of the hand is moved one second to the right of the ver- 
tical to make it point to the 60 at the end of the minute, (shown 
by the line from a to 60,) it would point to 30 two seconds too 
soon, i.e.^ it would gain 2 seconds in a half minute, and lose 2 
seconds in the next half minute, and keep on see-sawing that 
way all the time — a rather poor reliance for timing. 



THE WATCH ADJUSTER' S MANUAL. 75 

(166.) The hands. — See that the hands, and especially the 
seconds-hand, do not run too close to the dial, although the 
point of the last should be as close as is safe; that they do not 
touch nor run too close in the dial holes; that the minute-hand 
comes exactly on a minute mark when the seconds-hand is at 
60; that when the hour, minute and seconds-hand come over 
each other, at the XII or elsewhere, they cannot touch each 
other by any variation of their end-shakes; that neither of 
them can bind or get tight anywhere, but have sufficient free- 
dom in every position; that the minute-hand, center arbor or 
seconds-hand cannot touch the glass over the dial. Test this 
at their highest point of end-shake, and all around the circle. 
Any bent or unequal teeth in the escape wheel can be detected 
by the seconds-hand, if it stands in the centre of its circle and 
that is evenly divided. 

(167.) The pendulum. — See that the weight cannot come near 
the pendulum in any position, nor the pendulum too close to the 
glass in front, or anything behind or near it. Try this very 
carefully, if the pendulum is ever seen to "wobble" in the least 
degree while vibrating. Wobbling would indicate either that 
the escapement is not in good condition, (generally a sliding 
contact on the pendulum, from front to back,) or the suspen- 
sion spring has been twisted or bent, and been kinked, or is 
still so. If you caftnot correct the cause, be sure that the wob- 
bling pendulum cannot possibly touch anything; if it does, no 
reliance can be placed on its rate. If the wall or support is 
subjected to any jarring, it will cause more or less wobbling. 

(168.) Winding. — Before beginning to wind, press the key 
gently backward^ to see that the maintaining click and spring 
are in action, as the clock might get from 10 to 30 seconds 
behind while winding, if the maintaining work did not operate, 
(164), and even stop running. If correct, the spring will be 
felt to yield a little under the pressure spoken of, and while you 
are winding the seconds-hand will continue moving forward. 
But if the seconds-hand stops or ticks backwards when you 
begin to wind, it must be seen to at once. 

(169.) Position. — The regulator must be protected from the 
trembling, shaking and jars, especially those recurring at regu- 
lar intervals, as their period might coincide with that of the pen- 
dulum vibrations, and greatly affect their extent and consequently 
the rate. It should have as solid and firm support as can be 
obtained in the store. It should also be protected from change 
of temperature as much as possible — particularly from sudden 
changes, which may affect the rate before the compensation 



76 TH'E WATCH ADJUSTER'S MANUAL. 

acts. Artificially heated rooms are generally much warmer near 
the ceiling than near the floor, especially with low ceilings, and 
the upper pait of the rod and the suspension spring are more 
affected than the bob, making the compensation irregular. 
The coolest place in the store would seem to be best in this 
case — where there would be the least accumulation of warm air 
near the ceiling — or else a position where the bob would be ex- 
posed to radiation from warm surfaces in proportion to the 
warmth of the room at the top. 

Other Means for Keeping Standard Time. 

(170.) Box Chronometers are very frequently used by watch- 
makers for keeping standard time where they have not a first-rate 
regulator. These can be rated by the makers as closely as de- 
sired, and are better than ordinary regulators, being more uni- 
form and less affected by external disturbing influences. In 
almost every city there are chronometer makers or adjusters 
who will either sell or hire out instruments to watchmakers for 
timekeeping purposes. 

(171.) Secondary Clock. — It is frequently inconvenient to stand 
before the regulator when comparing time, and especially so for 
the springer and adjuster, or even for winding and regulating 
custom watches. In order to compare closely, it is necessary 
not only to be directly in front, but the eye should be nearly 
on a level with the clock dial to prevent mistakes when the 
minute-hand gets near the III or the IX, or the seconds-hand 
near 15 or 45. It is altogether better, therefore, to have a clock 
specially for timing purposes, arranged where it will be conven- 
ient for ordinary work. A good half-seconds regulator is pre- 
ferable, with perfectly spaced dial circles, and hung low on 
the wall, so that the workman can take his observations while 
sitting at the bench or at the watch rack. This can be regu- 
lated and set daily, or as often as necessary, to get the time and 
even the vibrations synchronous with the regulator or standard. 
It ought to remain synchronous at least one day, or half a day. 
As before stated, it is imperative that the standard shall always 
be placed in the most favorable position for securing accuracy 
in its rate, and where it can have a firm support and be undis- 
turbed. The regulator is for time, and the secondary is for 
timing, i.e.., for everyday regular use, the same as the bench 
tools, and it should be located suitably for such use. In large 
shops, two or more secondaries could be used, or electrical sec- 
ondary clocks employed. 



THE WATCH ADJUSTER' S MANUAL. 77 

(172.) Mirror arrangements or time reflectors. — Another 
great convenience, either with or without the secondary clock, 
is an arrangement of mirrors to bring an image of the clock dial 
directly on the bench, in front of the workman. It is often the 
case that when he is closely observing or manipulating a watch 
on the work bench, the clock is at one side or behind him, so 
that he cannot see both at the same time, to compare them. 
This is obviated by using mirrors. As one mirror always reverses 
the image, and the clock hand would seem to be moving the 
wrong way, and to be ahead of the 60 when it was really be- 
hind, and vice versa^ it is better to use two, and get a correct 
image, as that makes it unnecessary to acquire any new habit 
or to remember about the image being reversed, and so pre- 
vents mistakes. 

(173.) Proper position. — Supposing the clock to be on your 
right, the first mirror should be at your left, as nearly in front 
of, and level with, the clock dial as possible, in order to get 
a correct and undistorted image of the dial, the same as with 
the eye (171), but it can be inclined at any angle necessary for 
reflecting the image where it is required. The second mirror 
should be in front of you, at such level and position as will be 
most convenient for looking in it while working. Having 
found the best place for it by trial, make it a rule to always use 
it in that precise place, and then incline the first mirror so that 
it reflects the clock dial perfectly in the second, and incline the 
latter to reflect the image squarely to the eye. Both mirrors 
should be large enough to give a good view of the dial, and 
should be provided with brackets or standards to hold them se- 
curely in their proper positions. 

(174.) If the first mirror is to be used by two workmen, or 
by one at two places, its support should be provided with shoul- 
ders, notches or pins, so that it can be swung directly into 
either position and fastened there without any adjustment 
whatever. The second can be arranged similarly to hang up, 
or be supported on a sort of easel, and the places for its legs 
should be plainly marked on the bench, so that it can be at 
once placed in position. When not in use, the easel and mir- 
ror, rigidly fastened together, can be hung up out of the way. 
When mirrors are used, the clock can be hung higher on the 
wall than would be convenient for use without them. If the 
secondary clock has a pendulum marker (175), a single mirror 
will do to reflect the image to the eye. 

(175.) Vibration marker. — A good way to mark the exact in- 
stant when the pendulum vibration begins or ends, is to ar- 



78 THE WATCH ADJUSTER'S MANUAL. 

range a thin diaphragm or screen, say of tissue paper, in front 
of the pendulum bob, so as to obscure it somewhat except at 
the very end of each vibration, when its edge comes into full 
view. The bob is plainly visible all the time, but at the end of 
each vibration it suddenly becomes brighter, and thus marks the 
exact instant. If a half-seconds pendulum is used, the bob 
may be so exposed only at one end of the vibrations, and thus 
be equivalent to a seconds-pendulum for timing purposes, — for 
each brightening would correspond to the end of the vibration 
in a seconds pendulum. If the bob is not polished or bright 
enough for clearness, paint it over w^th varnish or size and 
bright bronze powder, either yellow or white, at the point of 
the bob which is to be visible. Even a bit of white paper can 
be glued on. The proper point is that which has the widest 
oscillation. The screen may be either inside or outside of the 
clock case. This method of observing the vibrations is even 
more convenient than by looking at a seconds-pendulum, and 
safer than listening to the tick, as that may be faint or drowned 
out by other noises. 



CHAPTER XIII. 

Means for Registering and Comparing Times. 

(176,) Apparatus for recording observations. — In the astronom- 
ical observatories, an electric recording chronograph is used, by 
which the exact instant at which any occurrence (as the pas* 
sage of a star before the wires in the eye-piece) takes place 
can be determined within a hundredth part of a second, or even 
less. This consists of a large cylinder which revolves upon its 
axis in exactly one minute, its speed being kept perfectly uni- 
form by a governor. A sheet of paper is wrapped around the 
cylinder, and two or more pens rest upon it, being arranged to 
be slowly moved by a screw from one end of the cylinder to the 
other, thus causing each pen to make a spiral line upon the paper. 
(When the paper is removed from the cylinder, the lines are 
straight.) The pen can be drawn sideways by a magnet, which 
can be actuated either by a clock or by an observer touching a 
key and sending a current through the magnet. Whenever 
this is done, either by the clock or the observer, the pen is 
drawn sideways, producing a notch in the line. One line and 
pen are governed by the clock, another by the observer, and 
so on. Half a dozen pens may be drawing parallel lines on a 
paper at the same time, like the lines on a sheet of music. The 



THE WATCH ADJUSTER'S MANUAL. 79 

one controlled by the clock makes a notch at the end of each 
second ; those controlled by the observers make their notches at 
the instants when a star crossed the line or some other event 
occurred, and was recorded by making the notch. The time of 
that event is found by comparing its notch with the time-notch 
made by the clock. If it is just even with the fifth seconds 
notch of the minute, it occurred at that second; if it is one-half 
(or one-twentieth) the distance between that seconds-notch and 
the next one, it occurred ^ or -^ second later — and so on. 
These lines are a permanent record, and the notches can be com- 
pared and measured at any time, and with any desired closeness. 
The clock does not close the circuit for making these notches by 
contacts on its pendulum, but by means of a special wheel 
on its seconds-hand arbor. The wheel has 60 pointed teeth, 
one for each second. Each tooth presses a lever sideways to 
complete the electric circuit, send a current, and make a notch. 
The foregoing gives a general idea of how the times are re- 
corded and compared. 

I had intended to fully describe the apparatus, and then sug- 
gest some less expensive modifications of it, suitable for use in 
comparing watches with the regulator, to ascertain precisely 
what difference there was between them. As the matter would 
only be useful to a very limited number of watchmakers, how- 
ever, I have concluded to omit it. But if any apparatus of 
the kind, adapted for more general use, should hereafter be de- 
vised, it will be described in this chapter, in some future 
edition. 

(177.) Pocket chronographs. — Meanwhile, the watchmaker 
can avail himself of apparatus already in the market, and make 
his observations and comparisons within % ox \ second, which 
is close enough for most purposes. By using a split-seconds 
watch, one hand can be stopped when the regulator reaches its 
60, and the other when the seconds-hand of the watch being 
tested reaches its 60 and its minute hand shows the same minute 
as the regulator. (161.) 

(178.) For observation of differences exceeding one minute, 
a minute chronograph can be used, if desired, but it is hardly 
necessary, for it is easy to note down the minutes by comparing 
the minute-hands of the watch being tried and the regulator, 
after finding the number of seconds they differ. 

(179.) Plain chronograph. — With a plain chronograph, it is 
only necessary to start it when the regulator reaches its 60, 
and stop it when the trial watch reaches its 60, then ascertain 
the number of seconds between the chronograph 60 and the 



8o THE WATCH ADJUSTER' S MANUAL. 

point of stoppage. If the trial watch is faster than the regu- 
lator, the starting must of course be done when its seconds- 
hand reaches its 60, and the stopping when the regulator 
reaches its 60. 'The difference or error should always be 
counted on the dial of the chronograph, as that of the trial 
watch may not be evenly divided off. 

(180.) Personal error of the observer. — It will be found that 
the hand of the chronograph will not indicate the exact instant 
of the occurrence, but will be a little behind, due to the ob- 
server not pushing the stud quite quickly enough, so that by the 
time the hand gets started it may be a quarter or half second 
behind. For instance, when the regulator hand strikes its 60, 
the intelligence of that fact is transmitted from the eye to the 
brain, there comprehended, an order sent to the finger to push 
the stud, the finger muscles contract and do as ordered, and 
even after the stud is entirely in, a little time is required for the 
chronograph wheels and hand to get in motion. The same 
error occurs with the professionals in the observatories, no mat- 
ter how experienced they are. Some will be quicker than 
others, but each one will have his own peculiar loss, whatever 
it may be. This is called the "personal error," and the error 
of each observer being measured and known, proper allowance 
is made when recording the observations taken by him. 

(181.) How to be correct. — In our cases, that error is of no 
consequence, because if we are Y-z second slow at the begin- 
ning we are also Y^, second slow at the end, and the difference 
between the two points is the same as if we had been exactly 
on the mark both times. Do not try to be quick, and exactly 
with the clock, for if you do you will not be alike but be quicker 
at some times than at others, and your observations will be uncer- 
tain and unreliable. Keep cool, be natural, take your regular 
gait, and the error will probably be the same every time, which 
is the most important point. Test yourself by the regulator, 
till you get your error alike every time. In setting watches to 
time, the same delay occurs. You should therefore start the 
watch a little too soon, and then touch the balance an instant 
to delay it a fraction of a second and so get the watch just 
right. 



THE WATCH ADJUSTER'S MANUAL. 8i 

CHAPTER XIV. 

Calculating the Proper Number of Vibrations. 

(182.) To find the number of vibrations per hour which a 
watch should give. As the wheel which carries the minute 
hand (generally the centre wheel) revolves once an hour, we 
take that as our starting point in all calculations. Count the 
number of teeth in the centre, third, fourth, and escape wheels, 
multiply these numbers together, and double the product, be- 
cause there are two vibrations to each tooth of the escape 
wheel. Count the number of leaves in the third, fourth, and 
escape-wheel pinions, and multiply these numbers together. 
Then divide the product of the teeth by the product of the 
leaves, and the quotient obtained will be the number of vibra- 
tions per hour. Thus, if the centre wheel has 75 teeth, the 
third wheel 64 teeth and its pinion has 10 leaves, the fourth 
wheel has 60 teeth and its pinion 8 leaves, and the escape wheel 
has 15 teeth and its pinion 6 leaves, it can be written out as 
follows: — 

75X64x60X15X2 ^ , ^ , 

-^ — -^ =18,000 beats per hour. 

10X8X6 ' ^ 

By cancellation, as above, much multiplying can be saved, 
and the operation made easy, short and quick. 

(183.) To find the number ofi vibrations per minute^ the surest 
way is to calculate the number of vibrations per hour, as 
above, then divide that number by 60 (minutes in an hour), as: 
i8,ooo-f-6o=3oo vibrations per minute. The whole can be 
done at one operation, by adding 60 as a divisor to the formula 
in section (182), thus: 

75X64X60X15X2 

10X8X6X60 -^ 

(184.) Afiother way. — Many workmen start with the fourth 
wheel, which revolves once per minute, count the teeth of the 
fourth and escape wheels, multiply those numbers together and 
the product by 2, then divide that by the number of leaves in 
the escape- wheel pinion, thus: 

60X15X2 ... . ^ 
-^ =300 vibrations per minute. 



82 THE WA TCH ADJUSTER'S MANUAL. 

In doing so, they assume that the fourth wheel revolves once 
in 60 seconds. But that is not always the case, even when 
there is a seconds-hand, and therefore this method is not en- 
tirely reliable, but the preceding one is. 

(185.) To find the number of revolutions of the fourth wheel per 
hour. — The first point to determine is whether the fourth wheel 
revolves 60 times per hour, i.e.., once in 60 seconds. Count the 
number of teeth in the centre and third wheels, and multiply 
the numbers together; then count the leaves in the third and 
fourth wheels, and multiply; lastly, divide the product of the 
teeth by that of the leaves, and the quotient will be the num- 
ber of revolutions per hour, thus: — 

75X64 _ 



10X8 



60. 



(186.) To find the number of seconds per revolution of the fourth 
wheel. — When the wheels are accessible, count the teeth in the 
center and third wheels, and the leaves in the third and fourth 
pinions. We might then ascertain the number of revolutions 
the fourth wheel makes in an hour as in the preceding section, 
i.e.., in 3,600 seconds, and find the number of seconds to one revo- 
lution by dividing 3,600 by the number of revolutions per hour. 
But we can make one operation of it by inverting the numbers 
shown in section (185), and adding 3,600 as a multiplier, i.e.., 
multiply the number of leaves in the third and fourth pinions 
together, and multiply that by 3,600, then divide by the pro- 
duct of the teeth of the center and third wheels, thus: — 

10X8X3600 

— = 60 seconds per revolution. 



75X64 

When the center and third wheels cannot be counted, this 
method cannot be used; but if the fourth and escape wheels 
can be reached to count them and the number of vibrations 
per second is known, the following way can be followed. 

(187.) To find the number of seconds to one revolution of the 
fourth wheel. — Count the teeth in the fourth and escape wheels, 
multiply these numbers together, and multiply the product by 2, 
then divide by the number of leaves in the escape-wheel pinion 
multiplied by the number of beats per second. Thus, if there 
were 5 beats per second, and the train was the same as before, 
we could put it in this form: — 

60X15X2 ^ , , . 

. -^ = 60 seconds per revolution. 

6X5 



THE WA TCH ADJUSTER'S MANUAL. 83 

(188.) Another way, by the seconds-hand, is to start the 
watch exactly with the regulator, when the seconds-hands of 
both cross the 60, run the watch till its seconds-hand again 
reaches its 60, and observe the number of seconds on the regu- 
lator dial at that instant. If the regulator shows i minute and 
12 seconds (or 72 seconds) during one revolution of the watch 
hand, we have this proportion: number of seconds indicated on 
the regulator dial is to the number on the watch dial as the 
number of seconds for one revolution of the regulator hand is 
to the number per revolution of the watch hand, which ^we 
write thus: — 

72 : 60:: 60 : jc, the unknown quantity. 

Multiplying the two extremes together, and the means together, 
we find that x is equal to 50, and the seconds-hand (and fourth 
wheel) therefore revolved in 50 seconds. It is necessary to wait 
till the watch hand gets to its 60, rather than to observe the 
number of seconds it shows at the end of one minute by the 
regulator, because the circle on the watch dial may not be 
evenly spaced off. 

(189.) Another way, when there is no seconds-hand, but the 
fourth wheel can be seen, is to make a slight mark on one 
tooth, and observe the number of seconds (by the regulator 
dial) during one revolution, i.e., from the instant that the mark 
passes some fixed point of the movement, close to it and easily 
seen, till it again passes the same point. Then arrange the 
proportion as in the preceding section. This gives the re- 
quired result without any counting of teeth and leaves, which 
might necessitate taking the movement apart. The mark 
should be brought exactly at the point convenient for close ob- 
servation, stop the balance and hold it there till the regulator 
hand touches its 60, then start it. 

(190.) To Jind the number of vibrations to one revolution of the 
fourth wheel, when not convenient to count the teeth and 
leaves, but the fourth and escape wheels are visible. Make a 
minute mark (unless there already is some mark or stain 
plain enough to answer the purpose) or put a speck of rouge or 
whiting on the rim of the fourth wheel; stop the watch and put 
a similar speck on an escape wheel tooth exactly over the other 
mark. When the two marks exactly coincide start the watch, 
and count the number of times the escape wheel revolves till 
the mark on the fourth wheel gets exactly to its starting point. 
Let us suppose that the escape wheel has 13 teeth, and that it 
revolved 10 times and 2^2. teeth over, /.^.,. instead of the marked 



84 THE WATCH ADJUSTER'S MANUAL. 

tooth standing exactly over the mark on the fourth wheel, it 
had passed 2 teeth and half a space beyond that mark. Then 
we have 13X io=i3o-|-2^=:i32^ teeth, which we multiply by 
2 (as there are 2 vibrations for each tooth), and thus get 265 
as the number of vibrations which that movement gives for one 
revolution of the fourth wheel. 

(191.) To find the number of vibrations per second. — This can 
be done by modifying either of the preceding operations. 
After finding the number of vibrations per hour (which is 3,600 
seoonds), divide that number by 3,600, thus: 18, ooo-^3, 600=5. 
Or divide the number of vibrations in a minute (which is 60 
seconds) by 60, thus: 300 -^6o=5. Or it can be counted with 
the aid of the regulator (198), or of another watch (214), or a 
timing balance (218). 

(192.) Another way is to make it a part of the original calcu- 
lation of the number of beats per hour or minute. In the case 
stated in section (182), we write it out as follows: — 

75X64X60X15X2 _ 

10X8 X 6 X 6oX6o~^' 

In the case stated in section (187), for finding the number of 
seconds to one revolution of the fourth wheel, we omit the 
division by 5 there given, and simply get the number of vibra- 
tions per revolution, by calculating the train as there described, 
and add the division by 60 to get the vibrations per second, 
thus: — 

60X15X2 

^ — — — c vibrations per second. 

6x60 ^ ^ 

If it is known that the fourth wheel makes one revolution in 
60 seconds, this result will be correct. 



CHAPTER XV. 

Counting the Vibrations. 

(193.) Counting the vibrations of the balance during a known 
period of time, as one minute, or one second, is the quickest 
and easiest way to ascertain whether a watch is running cor- 
rectly, or if a spring is suitable and will give the number of vi- 
brations which calculation has shown that the train should give. 
(See Chapter XIV.) The workman should therefore familiar- 
ize himself with the different ways of counting, and find which 
is best adapted for each particular purpose for his use, as the 



THE WATCH ADJUSTER' S MANUAL. 85 

temperaments and mental constitutions of different workmen 
will often render a certain method difficult for one workman to 
follow, when another workman will find it the easiest and best 
for him to work by. 

(194.) Vibration registers. — As it is difficult for some to count 
up to 300 or 400 vibrations without error, many workmen use 
some sort of recording apparatus for registering the number 
counted, so that they can count more easily, and do not depend 
on memory for the final result. There are several kinds, but 
they all have a key or push-piece, which is pressed at the 
proper times, and advances a wheel inside by one tooth for each 
pressure, carrying forward a hand over the dial and indicating 
the number of pressures. The workman counts the vibrations 
up as far as he can do so easily, and without any risk of mis- 
take, then makes a pressure, and begins to count a new series. 
Some can easily count up to 50 with perfect safety, while others 
are liable to get the number wrong if they go above 10 or 20. 
As there is no necessity for going so high that the mind is ab- 
sorbed in mere counting, it is generally preferable to stop at 
10. Anybody can do that almost automatically, and can at the 
same time give their thoughts to watching the behavior of the 
balance and other parts. 

(195.) Using the register. — Having his finger on the push- 
piece, and the hand pointing to o, he counts the vibrations 
up to 10, pressing the push as he says "Ten," then counts 
another 10 and gives another pressure, and so oi> to the end 
of the minute (or half-minute), noticing how many he had 
counted (after the last pressure) when the minute ended. If it 
was 8, and the dial showed 29 pressures of the finger-piece, 
that would give 29 x 10=2904-8=298 vibrations. If the spring 
ought to give 300 vibrations in a minute, this would show that 
it loses 2 beats (or -f second) per minute. 

(196.) Registering the vibrations with pencil. — With a little 
practice he can register the vibrations with only a pencil and slip 
of paper, so placed that he can make a plain mark without 
looking at it. Then at the end of each series of 10 vibrations 
he makes one mark, the same as described for pressing the 
push-piece, and the final result is figured out in the same way. 
The only difficulty is to avoid marking twice in the same place, 
and getting a false result. To avoid this, he should not only 
move his hand a little forward each time, but make the marks 
inclined alternately forward and backward. Even if he should 
happen to mark twice at the same place, one mark would not 
be over the other, but across it, forming a letter X, and pre- 



86 THE WATCH ADJUSTER' S MANUAL. 

venting any miscount. At the end of the minute, write down 
the surplus beats (those counted after making the last mark), 
then count the marks and write the number before the odd 
beats. Thus, if there were 2 extra beats and 31 marks, write 
down 2, and then 31 before it, making 312 beats altogether. 

(197.) To begin counting. — You would naturally say "One" 
when the minute begins, then " Two" at the next beat, and so 
on. But in reality, when you say "One," there has not been 
any vibration yet, and so you will get one too many. One 
vibration in a minute makes four or five minutes per day. To 
prevent this error, first say " Naught, one," then go on counting. 
Thus: "Naught, one, two, three, four," etc. The "naught" 
means you are only beginning to count; the second word, " one," 
shows one vibration made and counted. This correction is only 
needed at the begifining of the minute; after that, you say: 
" Eight, nine, ten, ®ne, two, three," etc., as usual. When count- 
ing by eye, arrange the watch so that an arm of the balance 
will be clearly seen at the end of each vibration. If the vibra- 
tions are not just one turn, the arm will be in a different place 
at each end of the vibration. Hold it so that you can see it 
plainly in both places, and begin counting with the one you see 
at the beginning of the minute. 

(198.) To commence the minute. — After getting everything 
arranged so you can see it conveniently as above stated, get 
ready to observe the regulator hand in the mirror, (172, 173,) 
at the beginning of the minute. A good way to know when 
the regulator seconds-hand is just at the 60 without looking is 
to look at it five seconds beforehand, after getting the seconds 
intervals in the mind so that you can count the seconds (or 
swings of the pendulum) without seeing them, then mentally 
count the seconds to the end of the minute, while you are get- 
ting the motions of the balance well in your eye, and at the 60 
begin to count the vibrations. Thus, looking at the clock (in 
the mirror), when its seconds-hand reaches 55 seconds you say, 
"Five," looking at your watch, and at each second's interval 
you say — either aloud or mentally — " Four — Three — Two — 
One — Naught, "and begin to count as directed in section (197). 
The " Naught" indicates both the instant that the regulator hand 
strikes its 60, and the beginning of the counting of the vibra- 
tions. To distinguish the clock seconds from the number of the 
vibrations, the former begins with a capital letter; thus "Five — 
Four — Three — Two — One — Naught, one, two, three, etc. A 
little practice will make this easy, and the habit will be found 
a very valuable acquisition. The workman will even get so 



THE WATCH ADJUSTER'S MANUAL. 87 

accustomed to carrying the regular periods in his mind that he 
can close his eyes for a short time, and continue the counting 
so accurately that his words will still coincide with the vibra- 
tions when he opens his eyes. Counting aloud will be found a 
great aid, and conducive to accuracy, although not absolutely 
necessary. Continue to count aloud while you lift your eye to 
the regulator hand, and notice the exact instant that it reaches 
the 60 at the end of the minute. 

(199.) Counti7ig alternate vibrations by eye.—h.s many work- 
men find it difficult to count every vibration^ an easier way is to 
count only every other vibration. For every vibration to the 
right there is one to the left. By counting only those to the 
right, (or to the left, if that will be easier for you), and doub- 
ling the number counted, you have the total number as before. 
It is well to become accustomed to counting both ways, so that 
you can begin the count with the vibration which occurs at the 
instant of beginning. If that happened to be a vibration to 
the left, count the left vibrations throughout the minute, and 
vice versa, making a pencil mark (or pressing the stud of the 
register) at each 10, as already described. If you had counted 
7 extra (after the last mark was made) at the end of the 
minute, that would mean 14 vibrations, and 16 marks would 
mean 160X2 = 320 vibrations, making 334 in all. If you were 
counting the left vibrations, but the last vibration of the bal- 
ance was towards the right, that would require the addition of 
I to the number of pairs counted. In the above case, you 
counted 160+7 ==167 pairs, equal to 334, to which add i, mak- 
ing 335- 

(200.) Counting the vibrations by ear. — When the watch is 
cased, it can be held to the ear, and the vibrations counted 
while the eye is on the seconds-hand of the clock, either 
directly or in the mirror (173). It being a little difficult to pro- 
nounce the numbers fast enough to count every vibration, it 
will be found easier to pronounce every other number, omitting 
the others. Instead of saying: "naught, one, two, three, four, 
five," etc., pronounce only the even numbers, thus: "naught, 
two, four, six, eight, ten, two, four," etc., omitting the "naught" 
after the start, i.e., saying it at the instant that the regulator 
hand crosses the 60, but not afterwards — and making a pencil 
mark at each "ten," as before, which can be done without look- 
ing at the paper. As the clock hand reaches the 60 at the end 
of the minute, notice whether it does so on the beat you are 
counting or the one whose number is not spoken; if on the 
latter, add i to the number counted. For instance, if there 



88 THE WA TCH ADJUSTERS MANUAL. 

were 28 marks, and you counted four after the last mark, be- 
sides the odd vibration, that would make 285. Of course, this 
method can be used by eye, instead of that in section (199) if 
preferred. 

(201.) Counting alternate vibratio7is by ear. — Some may prefer 
to count only the alternate vibrations, but calling off all the 
numbers, as described in section (198), for the sake of uniformity 
of method, if for no other reason. In that case, when the 
regulator hand crossed the 60, they would say: "naught, one, 
two, three," etc., to "ten, one, two, three," etc. If there 
were 285 vibrations, as in the last section, there would be 14 
marks, two over, (i.e., two pairs,) and the odd vibration, which 
would be figured up thus: 14X 2 = 28o-j-(2 X2)= 284-1-1 = 285, 

(202.) In this method of counting (by ear) there are two 
points which require some practice, (i), to ignore the alternate 
beats in counting, and count only every other beat, and (2), at 
the end of the minute, to notice whether the minute terminated 
on the beat you counted or on the alternate beat which came 
after it. A little practice and care will enable you to do both, 
without risk of mistake. 

(203.) Aids in counting vibrations by ear. — When the watch is 
not cased, its beat may not be loud enough to count by ear as 
above described. But there are various ways of reinforcing the 
sound and conveying it to the ear, which the watchmaker can 
adopt if desirable. A resonant box can be made of thin sono- 
rous wood, or of thin and elastic metal (even thin tin might do) 
of convenient size, say 6 inches long, 3 wide, and ij^ inches 
high, closed except one end, which is left open. If the move- 
ment is laid on this, the sound will be very much louder, espe- 
cially at the open end of the box. Putting it into any enclosed 
space with vibratory walls will greatly increase the sound. 
Even putting the movement in a pasteboard collar box without 
cover will often be sufficient. Another class of aids is a funnel- 
shaped piece, to be arranged over or close to the movement, to 
gather the sound, which is then conveyed through a rubber 
tube of any convenient length to a sort of hollow nipple, which 
fits snugly into the orifice of the ear. By having the funnel 
supported by a standard, and the nipple in the ear, both hands 
are left free for holding or working at the movement. Such 
apparatus can be obtained ready made from the telephone and 
phonograph people. 

(204.) Cou7iting for half a minute, instead of one minute, will 
often be sufficient to show whether your spring is suitable, at 
least for the preliminary trials, and it will lessen the number of 



THE WA TCH ADJUSTER'S MANUAL. 89 

vibrations to be counted. When the spring being tested is 
merely stuck to the balance staff by wax or putty powder, it 
will hardly bear more than a half or three-quarter turn vibra- 
tion without becoming loosened, or displaced from the centre, 
and of course will not continue to vibrate very long. With a 
good regulator, the half minute can be observed almost as 
closely as the whole. Another watch would of course answer 
in place of a regulator, provided it was closely regulated, with 
a large and plain seconds-dial accurately divided off, so that 
the 30 would be exactly 30 seconds from the 60. 

(205.) Counti?2g till reversal or coincidence of vibrations. — If 
you experience any difficulty in counting the beats and taking 
the time from the clock as described, you can simply count the 
balance vibrations till your balance reverses its motion, or re- 
verses twice and again coincides with a timing balance, as de- 
scribed in sections (218) to (222). After starting the two bal- 
ances together, count the vibrations till your balance gets 
ahead or behind enough to move in a direction opposite to the 
other, although its vibrations end at the same time as that. It 
has then gained or lost one beat in the number of vibrations 
counted. If that number was 300, your watch will vary one 
minute in 300, or nearly 5 minutes per day. If that number of 
beats was counted from the start till the balances again vibrate 
in the same direction and end at the same time, that would be 
gaining or losing 2 beats in 300, or twice as much as before 
stated. 

(206.) Counting the 7iumber of vibrations in one second. — First 
get the vibration or swing of the regulator pendulum well in 
the mind, so that you can nod your head in unison with it, i.e.., 
nod it exactly at the end of each swing (or second), and can 
continue this nodding correctly while you look at the balance 
and count the number of its vibrations between two nods. To 
test whether your nods are correct, continue the nodding after 
you have finished counting, and again look at the pendulum to 
see if the nods are still in unison with its swings. If there 
were 4 or 5 vibrations between 2 nods, each beat would of 
course correspond to ^^ or J second. If it does not seem to be 
even, count for 2 seconds; 9 beats in 2 seconds would be /\\ 
beats per second. Instead of counting the vibrations you can 
count the movements of the seconds-hand and find how much 
each movement means in time. This is often useful in timing 
a watch closely. 

(207.) Another way. — Some workmen reverse this process, 
and nod the head in unison with the balance vibrations (or 



90 THE WA TCH ADJUSTER'S MANUAL. 

movements of the seconds-hand), then look at the pendulum, 
to see whether the terminations of its swing all coincide with 
the downward motions of the head. If they do, there is an 
even number of beats per second. If not, continue the trial for 
several seconds, and if the swings to the right terminate with 
the downward nods, the number of beats is odd. This will 
help to determine the right number. A vibration-marker (175) 
is of great assistance, as it indicates the exact end of each 
swing. 

(208.) A7iother way is to count the number of vibrations of 
the trial balance (or the beats of the watch or movements of 
the seconds-hand), during 10 seconds by the regulator, and 
divide the total number by 10. This is the most reliable, and 
as easy as any, especially by nodding the head in unison with 
the pendulum (206). 

(209.) Timing bells. — Instead of counting the vibrations by 
a seconds-dial, as described, it can be done with the aid of a small 
clock arranged to strike a bell at the end of each minute. Sev- 
eral different arrangements of the kind are in the market, vary- 
ing in the details of construction and arrangement. Most of 
them give warning strokes a few seconds before the minute 
stroke, to prepare the workman. A similar arrangement could 
of course be attached to the secondary clock (171), and be 
operated by electricity, i.e.., the clock would close the cir- 
cuit, sending a current through wires to an electric bell, which 
could be placed wherever desired for use. Timing bells are 
very convenient in counting vibrations, but to be trustworthy 
they must give the stroke of the bell exactly at the right in- 
stant every time., and not be liable to strike a little sooner or 
later at some times than at others. A difference of one-quar- 
ter of a second between the initial and end strokes would be 
equivalent to 6 minutes per day in the running of a watch regu- 
lated by it. 



CHAPTER XVI. 

Testing Hair Springs. 

(210.) Testing by length of cone., or weighing the spring. — The 
most common procedure is to hold the outer coil of the spring 
in the tweezers, with the balance hooked onto the center, and 
see how far the weight of the balance will stretch the spring. 
The general rule is that the height of the cone (formed by draw- 
ing the center of the spring downward) should be about equal to 



THE WATCH ADJUSTER'S MANUAL. 91 

half the diameter of the balance. The outer coil must of 
course be held horizontally in the tweezers during the test. 
But this test is not of much aid, because a spring might be 
really of the same strength as the old one, and yet be drawn 
out much further or less by the balance, by reason of being 
proportionally wider or narrower than that. The stiffness of 
a spring varies in proportion to its width but as the cube of its 
thickness. But this test may answer for a first rough trial of 
a spring, to get some idea of its suitability. 

(211.) Testing ivith a hair-spring gauge. — For measuring the 
strength of hair springs there are several kinds of spring- 
gauges, and they are very useful in a watch factory, where a 
great many springs are required of practically the same size as 
to width, thickness, number and openness of coils, all fitted on 
collets of equal size, and pinned to the stud at the same place 
on the same coil. In such a case, measurement by a gauge 
will give the exact strength of each spring. The balances are 
also measured and weighed, to find their diameter of gyration 
and moment of inertia. Rules and tables are prepared from 
the results of trials and measurements of springs and balances 
in hundreds of movements, almost exactly alike, showing the 
best proportion between the spring and the balance. It is then 
easy by measurement of a spring to know whether it will be 
suitable for a certain balance, or to select a balance for which 
it will be adapted, so closely that when put together and timed 
they will not be more than a quarter or half minute out per day. 

(212.) But such gauges are of much less practical use to the 
ordinary watchmaker, who handles all kinds, sizes, and grades 
of movements, perhaps no two exactly alike, and has to select 
from among springs of equally promiscuous sizes, widths, and 
thicknesses, and to hold each one differently at each end. For 
his purposes, attaching the spring to the balance it belongs 
with, and holding the coils in my spring-fitting tool (238), or 
even in the tweezers, while vibrating the balance, will be fully 
as convenient, and will give closer and more practically useful 
results than the hair-spring gauge. In fact, the vibrating test 
will finally have to be used any way. Some springs require a 
large, open center, others one that is small and close; but the 
gauge makes no allowance for that. Those who wish to use 
them will find further information in Chapter XVIII., on fitting 
hair springs. Directions for using the tools are always fur- 
nished with them. For fitting springs in the usual grades of 
American watches the gauges are very convenient. 

(213.) Test by vibrating. — Temporarily attach the spring to 



92 THE WATCH ADJUSTER'S MANUAL. 

the axis of the balance for which it is intended, rest the lower 
pivot on some hard surface, hold the spring by its outer coil 
in such a way as to sustain the balance in a nearly horizontal 
position while resting slightly on the lower pivot, and count the 
vibrations it makes during a certain time, or during one or 
more swings of the pendulum; or compare them with another 
balance making the proper number. The latter is unquestion- 
ably the best of all the methods in use, not only for the first 
short tests, but also for the final long trials, and for regulating 
the watch quickly. 

(214.) Comparing balatices with a watch. — If you have a move- 
ment which makes the same number of vibrations that your 
spring ought to make, you can arrange its balance and the one 
you are vibrating close together, start them in unison, and see 
whether your balance gets ahead or lags behind. If you see a 
difference immediately, the spring will be so much too strong 
or too weak as to be totally unsuitable. If you only detect a 
difference by the end of a half-minute or a minute, it may be 
likely to answer, and if otherwise suitable you will be justified in 
pinning it in the collet and making a careful and decisive trial. 
Even after it is found correct, and finally pinned in the watch 
and running, the comparison of balances furnishes the easiest, 
surest, quickest, and best way of quickly bringing the watch to 
time. A difference of half a vibration can be detected with cer- 
tainty, which in an 18,000 movement would be y^^ second — a 
difference which could not possibly be detected by any other 
method available to the ordinary workman. If that error oc- 
curred in six minutes, it would only amount to 24 seconds in an 
entire day. For this use, the movement should be kept in a 
close, moisture- and dust-proof movement-box, and be closely 
regulated. It is not necessary to look at the hands, but take 
the time of beginning and ending the trial from the clock dial. 
Always keep a pencil and paper handy on the bench, for mak- 
ing memoranda. When you make a trial more than one minute 
in length, mark down the number of the minute when it began. 

(215.) To start the dala?ices synchronously. — Grasping the hair 
spring securely in the tweezers at the proper point, rest the 
lower balance pivot on the glass of the movement box at a 
point where that is horizontal, so that it will not slide down the 
inclined surface and interfere with the vibrations. It should 
also be where you can see both balances at the same time. 
Rest the hand holding the tweezers upon some support of con- 
venient height, so that you can hold it stationary without 
fatigue, and start the balance being tried in such a way that its 



THE WATCH ADJUSTER'S MANUAL. 93 

vibrations are in the same direction as those of the timing bal- 
ance and also begin and end at the same time with that. 

(216.) When in the movement. — Probably the easiest way to 
observe the vibrations of a balance, especially of a small and 
narrow one, is by noticing its terminations, /.<?., where it stands 
still for an instant while reversing its direction. When regulating 
a spring which is attached to a balance driven by the movement, 
so that its vibrations are of uniform extent, you should select 
an arm of the timing balance which is clearly visible at the end 
of the vibration, and arrange your trial balance as near it as 
convenient, with an arm ending its vibration just opposite to 
the other one, so that you can easily see both, then arrest the 
trial balance, draw it around to the above-mentioned stopping 
point, and liberate it so that it will begin its vibration in the 
same direction, i.e.^ just as it would if the two rims w^ere in 
contact — and at the same time, /.<?., they both reach the stopping 
point at the same instant. Then notice the time this trial begins. 

(217.) When not in the moveme7tt, this method would not be 
suitable if the test continued for more than a few seconds, be- 
cause the trial balance would rapidly lessen its vibration, and 
the arm would no longer stop where it could be compared with 
the other one. When making the first tests of a spring in the 
tweezers, it is better to arrange the two balances so that when 
both are at rest, i.e.^ at the middle of their vibrations, their 
arms will be in line and their ends close together. Let the tim- 
ing balance acquire its usual motion, then draw the arm of the 
trial balance around as far as is safe, and liberate it just at the 
end of the vibration of the timing balance, so that the arms of 
both balances will pass the line of centers together. With a 
little practice, this can be done very closely. In this case, you 
watch their motions at the line of centers (the line between the 
centers of the two balances) till your trial balance gets ahead 
or behind. If one balance is still while the other is at the 
middle of its vibration, the difference is half a vibration; when 
the arms pass together at the line of centers, but are going in 
opposite directions, the trial balance has gained or lost one 
vibration. If you are able to start them off exactly together, it 
is safe to calculate by the half vibration, or even less — as soon 
as you can see that your balance is getting ahead or behind. 
If you cannot do that, it is better to wait till their motions be- 
come opposite. For the preliminary tests of springs, the bal- 
ances can be more easily started together by using a timing 
balance specially intended for that purpose (218), instead of a 
watch movement. 



94 THE WA TCH ADJUSTER'S MANUAL. 

(218.) Twiing bala?ice. — For short tests of springs, the most 
convenient method is by what is called a timing balance, con- 
sisting of a balance on its staff and provided with a hair spring 
which causes it to make the number of vibrations required for 
trials. The balance pivots preferably run in jewels as usual, 
although brass holes will answer if kept clean and well oiled. 
But jeweled holes can generally be obtained from some con- 
demned watch, and the balance mounted on a small brass plate 
(say, two by four inches,) leaving vacant space enough at one 
end to rest the trial balance on the plate alongside of the other 
one. A balance with three arms and a plain rim is most useful. 

Arrange the spring on the staff so that one arm of the balance 
(the one which will be contiguous to the trial balance) will 
stand in the central line of the plate. In the same line make a 
series of shallow, flat-bottomed holes, large enough for the 
largest pivot to be free in, and, say -^-^ inch deep. This is for 
convenience of arranging trial balances at different distances 
from the timing balance, for comparing their arms while vi- 
brating. 

To prevent the timing balance changing its rate of vibration, 
no regulator should be used with it, but the balance should be 
brought to time by the hair spring only. Regulate it by a good 
watch; give it as large a motion as it can have without disturb- 
ing the regular action of the spring, so that it will vibrate as 
long as possible. Start it exactly with the watch balance (215), 
and see if they exactly coincide in direction and time till the 
timing balance nearly comes to rest. It is well to have two or 
three timing balances, giving the most usual numbers of vibra- 
tions, with the number engraved on each plate, as: — " 18,000 — 
300 — 5," " 14,400 — 240 — 4," " 16,200 — 270 — 4^," etc. 

(219.) To start sy7ichronously^ with timijig balance. — The best 
way is to arrange the two balances close together but not 
touching, with an arm of each balance in the line of centers 
(217) when at rest, then draw both balances around to the 
same distance, hold them till the proper time to start, and lib- 
erate both at the same instant, thus not only starting them ex- 
actly together, but with vibrations of equal extents. For hold- 
ing and starting two balances at once, mount two stiff 
bristles in a pegwood handle, with their ends sufficiently separ- 
ated for each one to engage with the arm of its own balance. 
Move each balance around and catch its arm behind one of the 
bristles. By lifting the bristles, the same motion liberates both 
balances. If the trial balance has only two arms, you can rest 
one bristle against the rim of the timing balance and the other 



THE WA TCH ADJUSTER'S MANUAL. 95 

behind the arm of the trial balance, and give them an equal 
start. 

(220.) Peculiarity of tiiTiing balance. — In testing springs with 
the timing balance, it should be remembered that it has no 
regulator, and therefore the point of the trial spring which is 
held in the tweezers when vibrating correctly is not the point 
where it should be pinned in the stud in the watch, but it corre- 
sponds to the point which falls in the regulator when in the 
watch. To find the position for pinning in the stud, make al- 
lowance for the distance between the regulator pins and the 
stud. When the spring is held in my hair-spring fitting tool, 
(233, 238,) which has got a pair of regulator pins and a false 
stud, the point in the spring which is held in the latter will of 
course be the place to pin it in the stud of the watch. 

(221.) Testing by opposition. — Having attached the spring to 
the balance (269), (270), either temporarily or permanently, 
start the two balances together, just as the regulator hand 
reaches the 60, notice whether the trial balance gains or loses, 
and when it terminates its vibration just as the timing balance 
is moving at full speed, notice the time on the regulator. The 
spring has then gained or lost a half vibration (217) in the 
number of seconds which had elapsed since the test began. 
With an 18,000 beat timing balance, one vibration is \ second, 
and half a bneat is -^-^ second. If the spring lost -^^ second in 
10 seconds, it would lose i second in every 100 seconds, or 
nearly a quarter of an hour per aay. In this way you can soon 
tell whether a spring is likely to answer. This method is not 
very close, and is only suitable for the first and coarsest trials. 

(222.) Testing by reversal.^ and by coincidence. — A better way is 
to continue the trial till the two balances end their vibrations 
at the same instant but vibrate in opposite directions, when 
your trial spring has gained or lost one beat on the other, in the 
number of seconds which had elapsed. This is called testing 
by reversal. A still better way is to keep on till they reverse 
again, so that the vibrations begin together and are in the same 
direction, i.e., they coincide as they did at the start, and the 
trial balance has then gained or lost 2 beats in the number of 
seconds occupied by the trial. Some can observe more easily and 
closely by one method than by the others, and each man should 
choose the one which is best for him, remembering that the 
longer the trial continues the closer the result will be. For, 
instance, if he makes an error of a half-second in taking the 
time from the regulator, and the trial was for 2 beats, the error 
would be only \ second per beat; if for 10 beats, only -^ sec- 



96 THE WATCH ADJUSTER'S MANUAL. 

ond, etc. The methods of testing given in this Chapter are 
somewhat easier than those by counting the vibrations, as de- 
scribed in Chapter XV., but some may prefer the latter. 

(223.) Quick test by comparing vibrations. — In the first rough 
trials, it is not necessary to continue any longer than till you 
see that your balance is gaining or losing on the timing bal- 
ance. If it does so within 20 or 30 vibrations, it will vary so 
much that it would not be suitable. After you find one which 
seems to vibrate with the timing balance for a considerable 
time, it will then be better to make a more formal test, as pre- 
viously described. 



CHAPTER XVII. 

Hair-Spring Fitting Tools. 

(224.) Excelsiors hair-spring fitting tool. — Although twenty 
years have elapsed since this tool was first described, I have 
never seen or read of anything equaling it in convenience and 
completeness. Yet, strange to say, no one has ever thought fit 
to manufacture it for the trade, although anybody is free to do 
so. There would certainly be a large sale for it, as every 
watchmaker who has occasion to do adjusting or testing needs 
something of the kind, and even for ordinary fitting of hair 
springs it would save much time and trouble. Its value having 
been fully demonstrated, I will again describe it, and also some 
modifications described in other horological works. 

(225.) The original tool was intended not only for fitting 
hair springs but also for upright drilling, setting and re-setting 
jewels, countersinking, chamfering, and many other uses. But 
I will here only describe it for the first purpose named. By 
using it, we may test a spring in every way without injuring it 
in the least, and in a very short time; so that, if it should not 
prove suitable for the watch on trial, it will still remain as per- 
fect for the finest isochronal adjustment in another watch as 
when made — a point of considerable importance when working 
with fine and costly springs. 

(226). Description. — It is substantially an upright holder, 
carrying arbors for different uses, and so constructed that the 
upright portion can be moved in any direction to bring the 
arbor over any hole in the watch, and there fastened. It con- 
sists of a clamp, to be fastened to the movement in any conve- 
nient place, carrying a round upright rod, movable up, down and 
on its own center, and having a head through which moves a 



THE WATCH ADJUSTER'S MANUAL. 97 

horizontal slide carrying the vertical arbors. The general idea 
of it is shown in Fig. 10, (233). 

(227.) The clamp is made from a thick piece of metal, (steel, 
cast iron or hard brass,) flat on its under surface, nearly rect- 
angular in shape, \\ inches long, by i inch wide, half an inch 
thick in the center and one-eighth inch at the edges, with one 
edge hollowed out to form two projections or claws, one at each 
corner, and about i^ inches apart. Under each of these 
claws there is a jaw, made something like the jaws on a uni- 
versal lathe chuck, capable of being fastened parallel with the 
surface of the clamp, and at any desired distance from it — so 
as to be screwed to the potance plate alone, or, if necessary, 
they can take in the whole thickness of the watch movement. 
The claws are slipped in between the bridges, or upon the plates, 
wherever a good bearing can be got, and the jaws screwed up 
to hold the clamp firmly in place — its flat under surface being, 
of course, in the same plane with the plate of the watch. The 
jaws can be faced with thin leather or rubber, if thought best, 
to give them a good hold without much pressure. In that case, 
they could be clamped directly on the dial without danger. 
My own tool is made double, having two claws i^^ inches apart 
as above, and on the opposite side of the clamp, two other 
claws or projections only \ inch apart, so that one side or the 
other will fit readily upon all sizes of movements. The jaws 
are also reversible, being turned at their center to point to- 
wards either pair of claws which are in use. 

(228.) Through the center of this piece or clamp is drilled a 
vertical hole to take an upright steel rod -^ inch in diameter, 
and about \\ inches long, having a head at its top, and fast- 
ened at any desired height by a screw, like the centers in a bow 
Jathe. In the head is a rectangular slot through which slides, 
horizontally, a steel strip \\ inches long, \ inch wide, and -^ 
thick, (a piece of an old pair of tweezers will do,) edge up, and 
fastened wherever desired by a screw. The strip also has an 
enlargement or head at its inner end, with a vertical hole to 
take in the different arbors to be used. These arbors may be 
the centers of your bow-lathe, or depthing tool, or any others 
you have already on hand, if you do not wish to make them 
specially for this tool. But I advise to use tolerably large ones, 
at least \ inch in diameter, so that the head will take in 
arbors for setting jewels, etc., if used for that purpose. But 
the arbor we use for hair-spring fitting should be reduced to a 
diameter of about -^ inch for three-quarters of an inch from 
each end, so as to penetrate into the smallest places, and also 
7 



98 THE WATCH ADJUSTER'S MANUAL. 

to enable us to bring our false regulator pins near to the center 
when wanted. One end should be brought to a fine central point, 
the other tapered down a little, and the end truly and centrally- 
countersunk. Or two sets of arbors can be made, one fine, the 
other larger, each having its own horizontal slide and head. 

(229.) The use of this tool is obvious. Having first fast- 
ened the clamp a firmly to some part of the movement, the 
upright rod b is inserted with its head at any desired height, 
and the horizontal slide d placed so that the point of its arbor 
f will rest in the balance jewel-hole, when the slides are 
screwed fast. We then reverse the arbor, /, and bring the other 
end, which has the female center, down upon the upper pivot 
of the balance (or any other piece you are fitting,) and hold it 
upright the same as would be done by the bridge itself. The 
angle of this female center should be rather acute, i.e.^ it should 
be deeper than it is wide at its mouth, so that it can be raised 
sufficiently to give the pivot freedom and yet not allow it any 
play sideways. The surface should be well polished and hard, 
kept clean and free from rust, and it will form a very tolerable 
substitute for the balance bridge. 

(230.) This arbor has two hubs, g and m^ which slide freely 
upon it, and are each fastened by a thumb-nut. In each of them 
is fixed a steel wire, i and 0^ -^ inch in diameter, pointing hori- 
zontally outward from the center of its hub. Each of these 
wires has a smaller hub, k and ?/, which slides to and from the 
arbor, and is fastened by a screw. One of them, «, has two 
points, to represent the regulator; the other, ^, has a clamp to 
grasp the hair spring instead of the tweezers, and therefore 
represents a stud. This clamp, k^ can be either self-acting and 
spring-tight, or be opened and closed by a screw. The points, 
y, are made thin, so as not to touch the adjacent coils of the 
spring, and both they and the regulator pins point vertically 
downwards. The two hubs k and /?, carrying the clamp and 
the pins, are adjustable independently of each other, as to dis- 
tance from the arbor, height, and distance from each other, to 
correspond with the relative positions of the stud and regulator 
in the watch. The wires which carry the two small hubs are 
filed flat on one side, making them half-round so that the set- 
screws can be loosened enough to allow the hubs to slide along, 
while they cannot turn over. If the spring on trial requires to 
be altered; we simply open the clamp to release it, and raise 
the arbor, when the balance can be taken out, and, after alter- 
ing, can be as readily replaced and refastened, everything being 
in the same position as before. 



THE WA TCH ADJUSTER'S MANUAL, 



99 



(231.) In my own tool I also had holes in different places, 
in any one of which a small plug, ^, with a milled head 
will fit — the plug being sawed through the center so that 
the two halves spring outward and hold the plug in any 
position in which it is placed. This plug carries a stiff bristle, 
and I place it in any hole suitable to the watch, so that 
by turning the milled head with the fingers I can lower the end 
of the bristle upon the balance rim, or raise it, in 
an instant, for the purpose of holding the balance 
still or liberating it. 

(232.) There may seem to be a good deal of this 
tool, but it is all 
perfectly simple 
and easy to con- 
struct, and any ; 
man fit to touch a 
watch ought to 
make one all complete 
in a day, at the utmost. 
If he has much work to 
do it will save him days 
and weeks of time, to 
say nothing of the satis- 
faction in its use, and 
the superiority of the 
work. Perfection is not 
required in any part for 
hair-spring fitting — the 
only point at all essential 
is that the arbor shall 
stand vertically or nearly 
so. There is nothing 
obligatory about any of 
the sizes or details 
given. The rectangular 
slot can be easily made 

by riveting together flat pieces, and leaving a space for the 
horizontal slide. But, whatever time may be required to make 
it, it is a tool for which every workman will find frequent and 
profitable use. 

(233.) Simpler forf?is of hairspring fitting tool. — Figure 10 is 
a sketch of a lighter and cheaper form, adapted only lOr hair- 
spring fitting. The clamp, <2, was made from a round piece of 
harness mounting, and the heads, c and e, from a piece of 




Lof 



100 THE WATCH ADJUSTER'S MANUAL. 

brass lightning-rod point, — showing how refuse scraps may be 
worked up into valuable tools and save cost. In this holder, 
the horizontal slide is a half-round rod, and the vertical arbor, 
/, is in line with the upright rod b^ both being vertical to the 
watch plate. But in the tool as previously described, the 
slide, (f/, was flat, to maintain the vertical position of the arbor,/. 

In this tool, « is a round clamp, with a thumbscrew, in the 
center on the back side, while the front edge is filed out to 
make the two claws; b is the vertical rod, with its head c, and 
set-screw, c'. This rod slides down in the space between the 
two jaws, u^ which are made from a broad flat piece of steel. 
The nut, r, runs on a screw fixed in the clamp, a, and the cen- 
ter of the nut passes through the jaws, to give more substance 
for the screw to hold in. The tightening screws, j-, are near 
enough to the center of the clamp to be bedded in the metal up 
to /, before coming out. The dotted lines, z£', represent a plate 
to which the holder is supposed to be fastened; d^ is the hori- 
zontal rod, with its head, ^, and set-screw, e'j f is the vertical 
arbor or runner, point upward. The holes are drilled entirely 
through the heads, c and ^, at right angles, one side of the cen- 
ter taking in the rods, which should be screwed in very tight 
and fast, — the other side taking in the set-screws; g is the 
hair-spring hub with set screw and smaller hub, k, sliding on 
the half-round wire, /, (which is filed flat on one side,) and 
is fastened thereon by the set-screw seen in front; J is a 
steel strip bent around the hub, k, to which it is fastened by the 
screw, k^ and terminating in fine points, j\ at the lower ends, 
which grasp the hair spring; / is a brass or steel piece riveted in 
the back half, to give substance for holding the screw, /', which 
draws the points together upon the spring. The small figure 
below is a transverse view of the same. Af is the regulator 
slide, with hub, ;/, sliding on the half-round wire, o, which is 
flat on the top; / is a brass strip which slides along the upright 
rod, ^, and turns in any direction, with plug, q, carrying a bristle. 
The set-screw of this strip is long enough to fasten it upon the 
rod, b^ d^ or/, — wherever it will be best to have it. All the 
parts are drawn in the best position for showing their construc- 
tion, not for use. 

(234.) Mode of using the tool. — Our Upright Holder being fas- 
tened to the movement so that the point of the arbor rests in 
the lower balance jewel hole, we select a spring for trial and 
stick it to the staff, then put the balance into its place in 
the watch. Reversing the arbor, or runner /, we bring the 
end with the female center down upon the upper pivot, 



THE WATCH ADJUSTER'S MANUAL. loi 

holding it in position, but leaving it free to vibrate. The 
hubs g and m having been previously slipped on the arbor 
and fastened by their set-screws, we place the hair-spring clamp, 
y, at the proper distance from the center to grasp the spring at 
the point which, before, we held in the tweezers, and fasten the 
whole properly. We then place the false regulator pins, n^ 
about as the real ones stand in the watch, or should stand, and 
fasten them also. Then we loosen the screw, e\ and turn the 
whole — the runner/, the spring in the clamp, and the regula- 
tor pins, «, — all together, and bring the balance in beat, or 
near enough for the watch to go freely, and fasten/ again. 

(235.) Testing the spring. — Lastl}^ we turn the balance a little, 
so that it will start off promptly on being liberated, and lower 
our bristle upon the rim to hold it so till we are ready to be- 
gin, then count the vibrations and proceed as directed in Chap- 
ter XVIII., except that we now shift the spring in the clampy 
instead of in the tweezers. If the number of vibrations is 
about right, we pin the spring to the collet, (273, 274,) and try 
again, shifting the spring if necessary till the correct number is 
obtained, then pin it in the stud at the point grasped by the 
clamp, put the watch together, and a very little regulation will 
finish the job. In this way you will never have to change a 
spring once pinned in the watch, for it is obvious that it will 
perform almost exactly the same there as in our Holder, pro- 
vided the regulator and stud occupied the same relative positions 
in each. In timing springs before breaking off the superfluous 
outer coils, the claws grasping the proper coil should be raised 
sufficiently for them to clear the other coils vibrating below. 
And, of course, the first trials should be made with a small vi- 
bration to avoid danger of loosening the spring in the putty 
powder. 

(236.) Peculiar cases. — Cases are occasionally found where the 
tool cannot be used exactly as described, and when it will be 
required to attach the holder clamp to the balance-bridge, 
place the upper pivot in its hole, and vibrate the balance by 
hand, counting, etc., as before. But these instances are ex- 
ceedingly rare, for in most English lever and other under- 
sprung watches the spring can just as well be stuck to the upper 
pivot for trial, while the balance is placed in the watch for run- 
ning as usual. And even after the spring is pinned in the col- 
let, that can be stuck on the upper side of the balance with 
putty powder, concentric with the pivot, and tested as before 
described, the balance receiving its motion from the movement, 
the same as if the watch was finished and going. 



102 



THE WATCH ADJUSTER'S MANUAL. 



(237.) Advantages of this tool. — As an error of one second in 
a minute will amount to 24 minutes in a day, it is important to 
be as exact as possible in our trials. In the usual method of 
fitting springs, where the balance is caused to vibrate only by 
the strength of the spring, counteracted by the staggering of 
the balance as it is supported by the stiffness of the spring itself 
as held in the tweezers, there is no possibility of any accuracy 
till the spring is actually pinned and tried in the watch. But 
with this tool, we may observe correctly from the start. The 



f^EZZli 




Fig. II. 

Breguet spring can be fitted in half the usual time with this 
tool, and done better, with no risk of injuring it by numerous 
trial pinnings in the collet and stud, which is almost unavoid- 
able while following the usual methods. It will also be noted 
that by raising the point of the runner/ out of the way, the 
balance bridge can be screwed in its place and the watch can 
run so, while the spring is still held in the false stud and the false 
regulator. This admits of exact position-timing in this tool. 
(238.) Excelsior' s improved hair-spring fitting tool. — The tool as 



THE WATCH ADJUSTER'S MANUAL. 



103 



previously described has a base piece, A^ arranged to be clamped 
on the movement or bridge which holds the vibrating balance. 
In many cases it would be preferable to have the tool stand on 
its own base, with conveniences for clamping a plate or move- 
ment firmly in position during the trial, similarly to an upright- 
ing or upright drilling tool. Fig. 11 shows abase, A^ of that 
kind, with a leg, 4^ at each corner for standing on the bench with 
the clamp screws, c?, free. Fig. 12 is a plan view, showing the 
base cut out at the center, z, with slots 2^ 2, 2, for the three posts 
or clamps, C, to slide to or from the center, for holding the 
movement in any desired position, like the clamps on the head 
of the universal lathe. 

(239.) Movement-holding clamps. — But the clamps may be 
very simple affairs. Fig. 14 shows one enlarged, being merely a 
brass rod turned out as shown at 6 and 7, with the screw 8 





Fig. 12. 



Fig. 13. 




firmly secured in its center. The part 8 slides in the slot 2 of 
Fig. 12, and the clamp is secured by the nut p, underneath the 
base plate A. The groove 6 may receive and hold either plate 
of the movement; the hollow 7 is to give room for the pillar 
plate, when the upper plate is held in groove 6. A washer, 10, 
should be used between nut p and the plate. The openings j, j, 
J, in the plate are to admit of seeing the watch dial, and noting 
the positions of the hands, without taking out the movement. 

(240.) The vertical runners or arbors. — The upright rod b should 
be of cast steel, of spring temper or case hardened, so that the 
screw a may hold it rigidly without marring its surface, and 
should of course be large enough to hold the head c and slide d 
with perfect rigidity. Instead of setting the runner/ in posi- 
tion by a male center or point on the other end of it, and then 
reversing/ to bring the female center down, a special pointed 
centering runner can be used. The rod b runs in a bushing B^ 
secured in the bed-plate A. 



104 THE WA TCH ADJUSTERS MANUAL. 

(241.) Sleeves for obviating repeated adjustments of parts. — B\ 
Figs. II and 13, is a loose sleeve which can be firmly secured 
on the rod b by thumbscrew a' . It has a hole fitting closely but 
freely over the pointed pin, 5, like a steady-pin, secured 
in the bushing B. When the rod b has to be lifted or 
taken out for any purpose, this arrangement insures that the 
runner / will be raised vertically upward and cannot twist 
sideways — and also that everything can be placed exactly 
in position without any readjustment. In first getting the 
runner / in position in the pivot hole, with sleeve B' loose 
and resting on -5, tighten thumb-screw a, then a\ thereby 
doubly securing the runner /against side motion. Also add 
a similar sleeve ^, on runner /, resting on the head ^, to be 
secured after / is properly adjusted on the balance pivot. 
This will admit of lifting /, and replacing it without read- 
justment, thus saving much time. The letters indicating the 
parts are the same as in Fig. 10, and the description thereof. 

(242.) It will be observed that not only can a spring be held 
and tested for length, number of vibrations, etc., in fitting a 
new spring, but the movement can be wound and run for any 
desired length of time, for regulating, testing the isochronism, 
etc. To see the hands, or set them, the tool may be inverted, 
or it can be held right side up over a mirror in which the hands 
can be seen. When it is to be inverted, or held in different po- 
sitions for timing, the runner/ should have a shallow cylindrical 
hole with flat bottom drilled vertically into its end, instead of 
the usual tapering hole, so as to avoid pinching the pivot when 
held inverted or edgewise, and enable it to run freely. Two or 
three runners or centers with holes of different sizes will suffice 
for all sizes of pivots. 

(243.) To time a watch when held in this tool, arrange the 
bristle holder, ^, Fig. 10, so that turning the plug will bring the 
bristle down on the balance and hold it, or lift the bristle and 
liberate the balance. When the watch seconds-hand reaches 60, 
stop the balance with the bristle, drawing it further around, if 
necessary, so that it will start off with a good motion when lib- 
erated ; then set the other hands. As the regulator hand 
crosses its 60, lift the bristle, and the watch starts off. If it is 
to be stopped at a certain instant, that is done by lowering the 
bristle. If the hands are merely to be compared, they are ex- 
amined by the mirror, or, if the runner has flat-bottomed holes 
as described, the tool with the watch in it can be inverted, for 
comparing times. 

(244.) Cheaper fitting tools can be made by altering over an old 



THE WATCH ADJUSTER'S MANUAL. 



105 



uprlghting or up- 
right drilling tool, 
in place of the 
base A — provided 
there is sufficient 
thickness of metal 
in the standard to 
sustain the screw 
holding the rod b. 
Rings can be used 
to raise the move- 
ment above the 
table, and plain 
clamps to hold it, 
if desired, as is 
done with the up- 
right drill, but a 
better way is to 
have three clamps 
or jaws similar 
to those on the 



]c' 



V 



DL 



a 



1 



f 



mm I 



W/ 



i 



w 



:« 



Fig. 15. 



a 



zr^ 



face plate of the universal or American lathe, and movable in 
slots like them. But the round sliding posts just described 
will do very well. 

(245.) Spring holder and clamp. — Fig. 15 is a rigid brass 

clamp, A^ to be fastened di- 
rectly to the watch plate or 
bridge, by thumb nut ^, having 
a loose washer on its point to 
avoid marring the plate by the 
screw. The rod b is rigidly 
secured to the clamp, vertical 
to the inner side of the clamp, 
and the head c is also fast on 
the rod, and carries the slide 
^, secured by thumbscrew c\ 
At the end of d is the head ^, 
carrying runner /, with spring 
clamp ^, as already described. 
The parts d, 
e and / may 
be made as 
described for 
Fig. 16. Fig. 11, and 




J^ 




io6 THE WATCH ADJUSTER'S MANUAL. 

SO be interchangeable in the different tools. The rod b may be 
two inches long, and the other parts in proportion. The slide 
^is half round, with the flat side vertical. The draughtsman 
has shown this tool twice the proper size. 

(246.) Standing spring holder^ or automatic tweezers. — Fig. 16 is 
simply a heavy base, A^ with rigid upright b and arm d, at the 
end of which is the head <?, carrying the sliding upright runner 
/, secured by thumbscrew as before. In this case, however, the 
lower end of the runner /is provided with a movable jaw k^ turn- 
ing on a pivot, both the jaw and the end of the runner being 
properly formed to grasp a hair spring like a pair of tweezers. 
The points are held together by the spring 6". The upright b is 
of such length as to bring the under side of e about three 
inches above the bench, on which this tool stands, in any con- 
venient position for holding the spring properly. The runner/ 
is made of the same size as those in Figs. 11 and 15, so that 
they can be used in this tool if desired. The tool is placed 
alongside of the watch, or wherever required, and the heavy 
base keeps it upright. If preferred, the arm d can be turned 
on the upright ^, but it is seldom necessary. 

(247.) Vibrating tools. — Special tools are also made, consist- 
ing of a hard polished enamel plate, an upright standard with 
an arm adjustable for height, a balance with a hair spring pinned 
in the arm as in a stud, arranged to make 18,000 vibrations per 
hour, (300 per minute,) as a standard of comparison. The 
trial balance is vibrated alongside of it as before described, be- 
ing held by the tweezers in the ordinary way. An important 
improvement would be made by mounting the timing balance in 
jewel holes, or at least giving the upper pivot of the balance 
some support while vibrating. 

(248.) Hair-spring gauges. — The one most familiar to work- 
ing watchmakers is Bottum's, which needs no description. Much 
more elaborate kinds are made, but they are principally for 
watch manufacturers. The ordinary gauge for the use of 
watch repairers is for ascertaining the relative strengths of all 
the springs in stock, so that a spring of any required strength 
can be readily found. Each spring is carefully measured by the 
gauge, then wrapped in a separate paper, marked on the out- 
side with the kind of spring, and the gauge-number showing its 
strength. In fitting springs, after one spring has been tested 
by vibrating, (Chapter XVI.) and not found satisfactory, its 
gauge-number, and the number of vibrations it gives are used 
for calculating the gauge-number which will give the required 
number of vibrations with that balance, according to the rule 



THE WATCH ADJUSTER'S MANUAL. 



107 



given in section (266). It is of course obvious that the springs 
must all be measured in the sa7ne gauge^ as any other gauge-num- 
bers would be useless. The Logan gauge, a well-known and 
widely used specimen of the tool, adapted for ordinary watch- 




FiG. 17. 

makers, is shown in the cut. Directions for use of course ac- 
company all gauges, and need not be explained here. 

(249). Spring-shaping tweezers ajzd pliers. — The tweezers are 
used for ordinary watch springs, and the pliers for the heavy 
springs of marine chronometers, which require more force to 
work them into shape. At the points, brass blocks are attached 
to the inner surfaces, one being made hollow, and the other 
rounding to fit into it. By heating the blocks, and then squeez- 
ing the spring between them, it is formed into a curve. Blocks 
formed to different curvatures are made, for making curves 
with more or less gradual changes of form. These are in- 
tended for making the terminal curves on Breguet and cylindri- 




FiG. 18. 

cal springs. Fig. 18 shows a pair of curve tweezers from Mr. 
Logan. Pliers are constructed in the same way, with wooden 
handles to prevent the heat from burning the fingers. 

(250.) Breguet spriftg benders are made in different ways. 
The simplest and cheapest are heavy tweezers having a small 



io8 



THE WATCH ADJUSTER'S MANUAL. 



pin near the point, and a pair of them further back, with space 
enough between the single one and the pair to receive the 
breadth of the spring wire. The pins fit in corresponding holes 
through the other point of the tweezers, so that when the 
tweezers are closed they pinch directly on the flat sides of the 
coil, while the pins prevent it from moving edgewise. The 
points of the tweezers are |- inch broad, and it would be ad- 
visable to have them curved inside to conform at least partially 
to the curvature of the spring coil. Fig. 19 shows elbow bend- 




FiG. 19. 

ing tweezers, as made by Mr. Logan. Two of these tweezers 
can be used to grasp the coil at the point where the elbow is to 
be made, and when the end of the spring has been bent up 
properly, shift them further along and bend it down, to get the 
supplemental coil level and parallel with the body of the spring. 
Or the edge of the spring can be rested on some convenient sup- 
port, and one of the curve-shaping tweezers (249) be used to 
hold the coil vertical while being bent. Directions for forming 
elbows and terminal curves will be found in the chapters on the 
Adjustment for Isochronism. 

(251.) Foisi?tg tools. — Different kinds are made, which it is 
unnecessary to describe. If desired, the workman could even 
file up two runners or centers to knife-edges, fitting into his 
depthing tool, in default of anything more convenient. Direc- 
tions for using are given in sections (300, 301,) of Chapter XIX. 

(252.) Various other tools are on sale, such as diameter gauges, 
tools for measuring the length of the cone formed in the 
''weighing" process, (210,) and some others, but as they are of 
but little assistance to the ordinary working watchmaker, they 
need not be described. 

(253.) Adjusting ovens and ice boxes will be described in 
the chapters on the Compensation, Part Eighth; a motive- 
force controller, in section (673); a little tool for holding the 
Breguet spring while working at it, in section (650); a move- 
ment-holder for holding the movement in any desired position 
while timing it, in section (699) ; a collet turner, in section 
(289) ; apparatus for hardening and tempering compensation 
balances has already been described in section (120). 



THE WATCH ADJUSTER'S MANUAL. 109 

CHAPTER XVIII. 
Fitting Hair Springs. 

(254.) The one chief criterion by which every spring must be 
judged is this: Isit suitable for the balance it belongs with ? If 
it is, the springer has but little more to do. If the balance it- 
self is not suitable for the movement, or if the movement is not 
in proper condition, no possible manipulation of the spring 
can make the watch a fine timekeeper; but if they are suitable, 
very ordinary skill will enable the springer to secure good time. 
He should therefore see to those conditions as a necessary part 
of his work, which he can readily do, as those points have been 
very fully treated in Chapter II of Part First, in Chapter X, 
Part Third, and in Part Fifth. 

(255.) Fitting the flat spiral spring. — I will give the method 
followed by good workmen in fitting the ordinary plain spiral 
spring. Fitting the Breguet and helical springs is fully treated 
in the chapters on Isochronism. It is not to be expected, of 
course, that pains will be taken to make the hair spring per- 
fectly isochronal, when the workman gets only $1, (which is 
the price in many places,) for fitting and regulating it. Never- 
theless he should have some regard for his own reputation, in- 
asmuch as it will be but little more trouble to approximate very 
closely to correctness, if he knows how, than to fit the spring 
in such a manner as to render its good performance impossi- 
ble. He will therefore understand that the directions to be 
given in these articles are essential to success, although I omit 
any discussion or explanation of the reasons therefor till we 
reach that part of the subject relating to isochronism. 

(256.) Proper cofidition of tools. — All tools used in working 
around hair springs must be kept perfectly clean and dry, not 
allowed to become magnetized, nor touched with soldering- 
fluid or other corrosive substances, nor should any such things 
be allowed on the watch bench at all. Their place is upon the 
clock and jobbing bench. A pair of fine tweezers must be kept 
solely for this use. The points should be very slim and thin, 
flat and rough on the inside, hard tempered, the jaws broad 
and firmly connected so that they cannot yield sideways and let 
the points pass each other, and made to come easily together 
without giving any more spring or stiffness at the points than is 
just necessary to hold the spring, or a pin. Too much strength 
is the cause of pins snapping away and other " accidents" that 



no THE WATCH ADJUSTER'S MANUAL. 

bother the beginner, who imagines that the tweezers should not 
only carry the pin to its place, but hold it firmly enough to 
force it in. They must not be heated and softened, nor used 
as a pin punch, for picking teeth, cleaning finger nails, prying 
off watch dials, or corks out of oil bottles, or picking the saw- 
dust out of keys, nor for anything whatever except working 
upon hair springs. But if the points do accidentally get in- 
jured, it will be a saving of time to put them in perfect condi- 
tion again before you undertake to work with them. The same 
remark applies equally to all other tools. There is no surer 
sign of a good workman than that his tools are always in per- 
fect working order. 

(257.) Rui7ied springs. — If a spring has been very much dis- 
torted, it probably cannot be made perfectly true in the coils, 
although it may be true in the flat, and if it belongs in a fine 
watch, another spring should be fitted. Even if a distorted 
spring should be worked on with the tweezers till it was re- 
stored to exactly its former shape, it would not act the same as 
before. Every place where it has been bent and restored will 
be of a different stiffness from the original, and every such 
place exerts a disturbing influence, rendering a uniform action 
of the spring impossible. An inexperienced workman will 
often render a spring worthless for fine time-keeping simply by 
numerous changes and corrections of shape. A spring should 
not be bent or altered any more than is absolutely necessary, 
and any changes of shape should be made by littles, rather than 
by bending too much and then having to bend part-way back 
again. The injury caused by bending is greater in soft than in 
hardened springs. Hence Breguet springs should always be 
hardened, because they necessarily have to be bent more or 
less in perfecting the terminal curves. 

(258.) Selecting a spri?ig. — In selecting a spring for trial, the 
repairer should be governed largely by the size, number of coils 
and cross-section {i.e.., shape of the wire) of the old spring, un- 
less you have reason to believe that it was not correct. The 
size is indicated by the position of the stud and regulator pins. 
The number of coils, if not known from the old spring, can be 
ascertained, for each kind of watch, by consulting Chapters in 
Part Fifth. 

(259.) The spring should have the same general form and 
sensitiveness to changes of temperature as the balance to which 
it is attached, i.e.., a wide and thin spring should go with a bal- 
ance whose rim is comparatively thin and wide, and vice versa. 
A spiral spring should be perfectly flat, evenly coiled, and pref- 



THE WATCH ADJUSTER'S MANUAL. iii 

erably with the coils becoming more distant from each other as 
they proceed from the center, being about twice as far apart at 
the outside as at the center (see Section (574;) and Chapter 
VIII;) the wire should be of an equal temper, breadth and 
thickness, throughout its whole length, well polished and free 
from rust. 

(260.) Enlarging a spring. — The diameter should generally 
be one-half that of the balance. If a spring cannot be found of 
just the right size, one of smaller diameter but having a suita- 
ble number of coils may be enlarged by the following process, 
which is also useful for spreading the coils apart when they are 
so close as to be liable to interfere with each other. Put the 
spring on a flat plate of either steel or brass, and over it 
another thin plate of bright steel, or, if of brass, with a har- 
dened steel screw in the center to act as a color-piece (81, 82.) 
Heat the whole very slowly and evenly till the top plate or the 
color-piece becomes blue, then let it cool, and it will be found 
equally expanded, unless the top plate has been too heavy to 
allow of free motion. If not sufficient it can be treated in the 
same way again — as the temper will not be reduced any lower, 
provided that the heat is not at any time greater than will blue 
the hardened bright plate or color-piece. 

(261.) Flattening a spring. — If a spring has been warped or 
bent out of flat, it may be flattened in a similar way, by fasten- 
ing it tightly between two steel plates so as to prevent expansion 
and blue the upper plate, which will cause the spring to " set" 
perfectly flat. But in all these cases great care must be taken 
not to exceed the bluing heat or, if the spring is of any other 
color, not to carry the color of the hardened color-piece be- 
yond the shade of the spring. When the spring has never been 
hardened and tempered, but merely rolled hard, it will open out 
too far and become too large when so treated. To prevent this, 
it should be wound up and the coils made closer and smaller, 
before heating. That can be done by the aid of the winding 
tool used in making hair springs (89 to 91), or by similar means. 

(262.) Bulged springs. — If the center of the spring has been 
merely sprung up, the best way is to take the collet off the bal- 
ance and slip it on your pin punch till it fits snugly, then take 
hold of the outer coil, or of the coil where the " bulge" com- 
mences, with a stiff pair of tweezers so that it can be firmly 
held horizontally, then push the center with the pin punch, in 
a direction exactly vertical to that in which you hold the outer 
coil, and the spring can generally be sprung back so truly as to 
be about as perfect as ever, and with very little trouble. 



112 THE WATCH ADJUSTER'S MANUAL. 

(263.) Hardeni7tg rolled or soft springs^ already made. — When a 
watch is found to have a soft spring, i.e.^ one which is not 
fire-hardened and tempered but only drawn and rolled, it can 
easily be hardened and tempered in its present form, by re- 
moving it from the stud and collet, taking out any accidental 
bends and getting it into correct shape, placing it centrally 
between two perfectly flat plates of copper, which are then 
screwed tightly together in the clamp shown in Fig. 6, section 
(120), heating it in the cyanide bath, {(i^, quenching in water, 
and tempering in an oil bath, or heating to a blue over a flame. 
If necessary, clean it in hydrochloric acid (60), again screw 
tightly in the clamp as before, being careful to get the screw cen- 
tral with the spring, lay a piece of steel on the upper plate, and 
heat very slowly till the steel comes to a blue. A spring so 
treated will have all the advantages of a hardened and tem- 
pered spring, and will time almost exactly the same as before — 
within a few seconds. The operation will expand the spring a 
little, and if that would be objectionable, it should previously 
be wound up in the spring box (90) to make it a little smaller. 
If the spring is of " mild" steel, it will require a higher heat to 
harden it (the last cherry red, (64,78), or it may be so mild that 
it cannot be fire-hardened at all. 

(264.) The number of vibrations. — In selecting a spring, it is 
necessary to know the number of vibrations it should make per 
minute or half-minute. This can be ascertained by counting 
the vibrations of that watch, or of one like it, for one minute. 
Directions for counting vibrations are given in Chapter XV, and 
for finding the number which that particular watch was intended 
to make, by counting the teeth and leaves of the train, in Chap- 
ter XIV. The general principle is as follows: — 

As the center wheel revolves once per hour, we multiply the 
numbers of teeth in all the wheels from the center to the es- 
cape wheels, inclusive of both, into each other, and divide that 
result by the product of the numbers of the leaves in the pin- 
ions of all those wheels (except that of the center wheel), then 
double the quotient, as there are two vibrations to each tooth 
of the escape wheel. This gives the number of vibrations the 
watch makes in an hour, and dividing that by 60 gives the vibra- 
tions in one minute. Whenever there is a doubt, or the watch 
is of an unusual make, it is well to count up and calculate as 
above. If you have a movement which makes precisely the 
desired number of vibrations, you need only try your spring 
alongside of that, as described in (219,) and any divergence 
between them will be seen at once, without counting. 



THE WATCH ADJUSTER'S MANUAL. 113 

(265.) Selecthig by hairspring gauge. — Many workmen select 
springs by measuring their strength in some spring-gauge. 
This gives no indication of the number of vibrations it will 
make, but is merely a certain gauge number, which is of little 
or no value unless it can be compared with the strength of the 
old spring measured in the same kind of gauge., or with a spring 
which has already been tested by vibrating it with that partic- 
ular balance, found not to give the proper number of vibra- 
tions, and then measured in the gauge. For instance, suppose 
that the spring, when stuck to the balance and vibrated, gave 
250 vibrations in a minute, when we required 300. Instead of 
sticking other springs to the balance and testing them in the same 
way till we find one to suit, as is usually done, we can test the 
strength of our first spring in a hair-spring gauge — Bottum's or 
Logan's is too well known to need description — and examine 
the rest of our stock of springs by the gauge, without attaching 
them to the balance, and find what we want by calculation, by 
the following rule: — 

(266.) Rule for using hair -spring gauge. — The forces of two dif- 
ferent springs., attached to the same balance, will be in the same propor- 
tiofito each other as the squares of the numbers of vibrations which each 
makes. Expressing this in the same way as was done in sections 
(133) to (137,) and taking 7^ to represent the force (or gauge 
number) of the spring, we would have the following formula : F^ : 
F^W V^ : V^. Supposing that the spring tried gave 250 vibra- 
tions, when we want 300, and in the gauge the strength is, say, 
20. Then our problem may be stated thus: If a spring which 
gives 250 vibrations per minute gauges 20, what must a spring 
gauge that will give 300 vibrations? According to our rule, 
the square of 250 will be in the same proportion to the square of 
300, (the desired number of vibrations,) as 20, the force of our 
present spring, is to the force of spring which will give 300 
vibrations — which is what we want to find out. We will there- 
fore represent that unknown force by the letter x during this 
calculation, and having squared 250 and 300 {i.e., multiplied 
each into itself,) we write the proportion down as follows: 
62,500:90,000: :2o:x. Now multiply the two end terms of 
the proportion together, and the two middle terms together, 
and the two products will be equal, according to the law of pro- 
portions. Multiplying, we get 62, 500X ^ =1,800,000, and by 
dividing we find that one x is equal to about 29, which is the 
gauge of a spring that will make 300 vibrations per minute; or, 
to express our process more methodically, ^= -^11-^^1-^= 29, 
nearly. Having found among our stock of springs one that 
8 



114 THE WATCH ADJUSTER'S MANUAL, 

gauges 29, we have but little more to do. Of course, any- 
other figures obtained by the workman in any particular case 
may be substituted for those given above. 

(267.) Allowance must be made for the fact that some springs 
will be used with a wide, open center, others small; some will 
be held in the stud by the outer coil, others three or four coils 
from the outside — to suit the watch — and of course they must 
be held at the same place while measuring their strength or 
vibrating them. 

(268.) The usual i7iethod of selecting a spj'ing is to lay the bal- 
ance bridge on the bench bottom upward, and with the regula- 
tor pretty well back toward the "slow," where it should be, 
then taking a spring which you judge likely to give the proper 
number of vibrations, (264), you place it on the bridge so that 
its center will come exactly at the pivot hole in the bridge, and 
one of the coils lying naturally and freely between the regula- 
tor pins. This coil can be marked, at a point about one-eighth 
of an inch back of the regulator pins, (/.^., nearer the stud,) 
with a speck of rouge or whiting mixed with watch oil. That 
is the point which must be held in the tweezers while vibrating 
the balance or measuring the strength of the spring in the 
gauge. It is also the point to be held in the false stud, when 
using any of the fitting tools described in Chapter XVII. But 
to avoid repetitions, I will describe the process as performed with 
the tweezers, since the same method is followed with the other 
tools. 

(269.) Vibrating the balance. — Having now put a little putty 
powder on the balance-staff, just below the shoulder of the 
upper pivot, (or the lower one, if more convenient, or on the 
shoulder where the collet goes), you stick the inner end of the 
spring to this putty, making a temporary but firm connection 
between the spring and the staff. Adjust the spring so that it 
will stand centrally and truly on the staff, then grasp it with 
the tweezers about one-eighth of an inch back of the point that 
lay in the regulator-pins, and, while the lower pivot rests on 
some hard, polished surface, you hold the balance upright by 
means of the spring, and cause it to vibrate. Care must be 
taken not to get so large a motion as to loosen the spring in 
the putty. By holding the coil in the tweezers pretty high, the 
spring can vibrate without coming in contact with the coils out- 
side of the one held in the tweezers. The hand is rested on 
some convenient support. Instead of using putty as above, if 
the center of the spring is very small, and will have to be 
broken out, any way, the central coil may be bent so as to hug 



THE WATCH ADJUSTER' S MANUAL, 115 

the staff tightly and dispense with the putty. But this should 
not be done when that coil will have to be bent back into shape 
again and used. 

(270.) Putty pouider for holditig springs is a great improvement 
over the common way by using wax, as it can be readily dis- 
solved off by placing in alcohol, and leave the balance perfectly 
clean. But nothing will thoroughly clean wax off except scrap- 
ing; it will not dissolve off. Doubtless, if the truth was known, 
thousands of stoppages and timing faults would be rightly 
laid to traces of wax left on the pivots and other parts, making 
them sticky, etc. 

(271.) Countijig the vibratio7is. — Full instructions for starting 
the balance at the instant the seconds-hand of the regulator 
crosses its 60 are given in the preceding Chapters of Part 
Fourth, and the reader will do well to carefully consider all of 
the methods of counting vibrations described — testing them if 
necessary for a full understanding of their meanings and merits, 
and then select those which will be best suited to his tempera- 
ment and facilities. He should not think that some of them 
must be superfluous because so many are described, for every one 
of them, is useful and valuable, either generally or for special 
purposes, and he will be the loser if he disregards them. The^ 
same may be said with respect to the other details of this book. 

(272.) Everything being in readiness, you set the balance in 
motion, and count the vibrations it makes in exactly one min- 
ute. It will be much easier if they are counted only in one 
direction, as from left to right; then double the number. As 
already stated in sections (221, 222), if you have a movement 
or a timing balance (218) making the proper number of vibra- 
tions, you can try your spring beside that, causing the two bal- 
ances to vibrate together at first, and notice whether your 
spring lags behind or goes ahead. In either case, count the 
vibrations from the start till they come together again. If 
your spring loses a beat or gains one in fifteen seconds or less, 
it is certainly not suitable. It should not lose or gain more than 
a couple of beats in a minute. Or you can rest the balance-pivot 
on the glass cover of a movement-box, directly over the balance 
going underneath, and readily compare the two. These trials 
give you definite information about the performance of the 
spring and its suitability for the watch, while the gauge will only 
compare it with some other spring. 

(273.) Pinning to the collet. — If the spring does not give very 
nearly the desired number of vibrations, or cannot be made to 
do so by shifting it in the tweezers a quarter, or half coil, it is 



ii6 THE WATCH ADJUSTER' S MANUAL. 

removed and another tried, and so on till one is found which 
meets the above requirements, when, in the case of a plain 
spiral spring, it may be pinned to the collet for a final trial. 
Aside from the convenience of using putty as described, for 
preliminary trials, there is a grave objection to pinning the 
spring to the collet at first. Collets differ much in size, and if 
a spring was cut out at the center to fit properly on a large 
collet, it would be greatly injured for any watch with a smaller 
one, if it did not happen to fit the one first tried. But with the 
temporary putty fastening no injury is done to the spring if it 
proves unsuitable. If it will be necessary, when pinning it to 
the collet, to cut out considerable of the inner end, additional 
length must be allowed at the outer coil to compensate for this 
shortening at the center — otherwise the watch will of course 
gain time. Springs are generally made small enough to fit the 
smallest collets, and often require considerable cutting to go 
on a large one. And if this additional length outside when 
allowed for would make the spring too large to lie freely in the 
regulator-pins, it must be rejected. This can be ascertained 
before cutting it, by again trying it on the inverted balance 
bridge. Before pinning the spring to the collet, see section 
(290) if the collet is not in poise. Also test the poise of the 
balance. 

(274.) The cent7'al coil. — The manner of pinning it to the col- 
let is important. There should not be a large vacant space at 
the center of the spring, but the inner coil should be only far 
enough from the collet to avoid any danger of touching it, even 
in the longest vibrations — but it must not be too close. We 
often find springs with the inner coil actually hugging the col- 
let — a certain proof that the watch has been in the hands of 
a botch. Either end of the pin sticking out so that the coil 
can hit it, is another evidence of botchwork. The inner end of 
the spring should be put into the hole in the collet entirely up 
to the elbow, where the straight joins on the curved portion. 
From the elbow the curve should diverge from the collet in 
such a manner that it will meet the regular spiral form in about 
one-eighth of a coil from the elbow. This is better than run- 
ning the spiral itself up to the collet, except when the coils are 
very wide apart, in which case the spiral should reach and be 
pinned directly to the collet. If the spring diverges too boldly 
from the collet, its action will not be good. On the other 
hand, if it diverges too slowly, it will lie so near the collet as 
to be likely to touch it when closely coiled up, or a minute 
speck of dirt wedged in between them would produce the same 



THE WATCH ADJUSTER'S MANUAL, 117 

effect. No portion of the spring, however small, should rest 
on the collet, or on any dirt upon the collet, or on any pin, nor 
should any coil touch another, even at the extreme end of the 
longest vibrations the spring will make in use. The repairer 
should examine every doubtful hair spring that passes through 
his hands, turning the balance that distance with the finger 
in each direction, and holding it still while looking over the 
spring. Although a little out of its order here, I would also 
say that the spring must not touch anything above, below or 
around it, except the collet, stud and regulator, and them only at 
one point. All workmen know that this should be so, but they 
cannot know whether it is so, unless they move the balance 
to each extreme and hold it while they look as above. It is 
very common for two coils to hit the regulator or the stud. 

(275.) Central coil too open. — If, however, there is more space 
at the center than is supposed above, the curve should take 
more length to reach the regular spiral portion of the spring, 
but in no case more than 90° or one-fourth of a coil. If that 
is not enough to reach the spiral, with a moderate divergence, 
the space is too large. The object we have in view is to bring 
the entire length of the spring, from the regulator to the collet, 
into action as uniformly as possible. Any considerable varia- 
tion from the spiral form at the center causes irregularity of 
action, i.e.., an action different from that of the rest of the 
spring, and the greater this variation the greater the resulting 
irregularity. In springs which diverge very boldly, or which 
have a large open space at the center, this sweep or curve be- 
comes a veritable "terminal curve," modifying the action of the 
whole spring, always difficult to change or adjust, on account 
of its position, and frequently defying every effort to neutralize 
its injurious effects upon the isochronism. It is even necessary 
sometimes to make the collet larger, or to change the spring. 

(276.) Pin the spring level. — In pinning the spring many 
workmen fasten the end "any way it happens," then bend the 
central coil up or down to make the spring stand truly, not 
knowing that as soon as it is flexed it will be thrown out of its 
true plane by reason of this central twist. The spring should 
always be leveled before the pin is tightened, so that when fast 
it will be true without any twisting. The pin should barely 
reach through the hole, not sticking out at either end, and par- 
ticularly not at its large end next to the elbow. It should be 
made either of hard brass or steel, stiff and tapering but little. 
After filing it up, flatten one side so that it will go in nearly as 
far with the spring in the hole as out, and while both are in the 



ii8 THE WATCH ADJUSTER'S MANUAL. 

hole mark where it projects from the collet on each side, cut it 
off at the end, file a notch around it at the other mark, then 
force it to its place and break it off while in the hole. The 
small end should not be pointed, but flat, so that it can readily 
be pushed back for altering, if necessary. For this purpose 
you want a special pin-punch, made from a short needle, per- 
fectly flat on the end, and firmly fixed in a substantial handle. 

(277.) Getting the spring level a?id concentric. — While pushing 
the pin in or out of the collet, you should hold the latter flat- 
wise (the pin-hole being outside of the end of the jaws), in a 
pair of pliers lined with soft iron or copper — by which you can 
hold it firmly without any need of marring it. The jaws also 
serve as guides in getting the spring flat. To try it, slip the 
collet on an arbor, and revolve it in the turns or calipers, either 
with a bow or with the fingers, noticing both the flat and also 
that the coils rise evenly from the center to the outside. But 
if, as your eye runs along the coil while it is turning, there 
seems to be any waving or "bobbing," the spring is not con- 
centric with the collet, and must be made so by altering the cen- 
tral coil. Being true both in the flat and in the coil, you now 
put the collet on the balance-staff, and again try if the spring 
is flat and true, by whirling the balance in the turns, or even 
between the thumb and forefinger. The collet must be ad- 
justed on the staff at such a hight that the spring, when 
pinned in the stud, will be perfectly level. If the collet end of 
the spring is higher or lower than the hole in the stud, the 
center will be bulged up or down, and satisfactory action will 
be impossible. It is important, for this reason, that the balance- 
staff itself should have no more end-shake than necessary. 

(278.) Pinning to the stud. — Before pinning the spring in the 
stud, you now verify its proper length more closely, by again 
counting the vibrations while holding it with the tweezers, 
remembering that the point which is to go in the stud should 
be about one-eighth to one-fourth of an inch beyond the place 
where it gives the correct number of vibrations in the tweezers. 
This is to allow for the effect of the regulator. (This allow- 
ance is not needed when my fitting tool is used. See Chapter 
XVII). The exact distance will be about one-third less than 
the actual distance from the regulator to the stud, along the 
coil. Having placed that point over the hole in the stud, 
while the pivot is in its jewel hole, the outer coil should lie 
freely in the regulator, and the elbow or end at the collet must 
occupy a certain position relatively to the stud. Why that posi- 
tion is preferable to any other might be hard to explain, but 



THE WATCH ADJUSTER' S MANUAL. 119 

experience has shown that it secures a better and more iso- 
chronal action, and it should therefore be adopted. 

(279.) Pin?iing in even coils or fractional coils. — The mode of 
pinning the ordinary flat spiral spring depends upon the escape- 
ment of the watch. If it is to go in a cylinder escapement 
watch, the spring should be pinned about half a turn short of 
even coils, i.e.^ if we draw a straight line through the center of 
the spring, the elbow or bend at the collet would be in that 
line on one side of the center, and the stud on the other side of 
the center. Thus it would generally have from 81 to un- 
coils. See section (397.) For a duplex watch the coils 
should be pinned in the same way, (427), but for a lever watch 
the spring should be pinned in even coils. See Chapter 
XXVII. For a chronometer, the flat spiral spring is not used. 
Directions for the Breguet and cylindrical springs are given 
further on in this Chapter; also see Chapters XXVII and 
XXVIII. 

(280.) Piiining in even coils. — For convenience of description, 
we will suppose that we are fitting a spring for a lever watch, 
and for any other kind the directions should be modified ac- 
cordingly. For a lever, then, the elbow (the end at the collet) 
of the spring should lie in a line drawn from the center of the 
spring to the stud. If it varies much from this position, the 
isochronism of the spring will be more or less defective. Al- 
though the time shown by the watch at the end of each 24 
hours may become correct, by dint of regulating, it will not be 
correct at any previous period, — nor afterwards, in case the 
watch is allowed to run over 24 hours before rewinding. It 
will either gain in the first 12 hours, and lose in the last 12, or 
the reverse, perhaps making a correct average for the entire 24 
hours. Such watches must be wound regularly, at precisely the 
same hour each day, to secure even fair time. And in regulat- 
ing them they must be timed at the end of each 24 hours, and 
at no other time during the day, as that would damage the reg- 
ulation instead of improving it. But no watchmaker who cares 
for his reputation should let a job go out in this condition. The 
correction of this error will be fully treated hereafter. See 
Chapters on Isochronism and Regulating. 

(281.) Manner of pinning. — But if the spring has been fitted 
as I have directed, you may proceed to pin it to the stud, with 
full confidence that it will perform satisfactorily. It should not 
have been done before, because at that point in the stud there 
is always produced a bend or crimp, by the pin forcing it to 
conform in shape to the hole, and if it should afterwards be 



I20 THE WATCH ADJUSTER'S MANUAL. 

necessary to let it out and bring the crimp into the acting por- 
tion of the spring, that stiff point would interfere with perfect 
performance. Even filing the pin flat on one side does not 
entirely prevent this. Hence it is advisable not to pin a 
spring unless it is reasonably certain that it will answer the 
purpose, and then it should be so pinned that it will surely be 
long enough^ and that any necessary alteration will be made by 
taking it up, or drawing it further through the stud, not by 
letting it out. A spring may be selected, fitted and partly reg- 
ulated in the watch before pinning it in the stud at all. But 
as springs occasionally need to be shifted, even after they are 
fitted, it might be a good idea in fine watches to pin them with 
a flatted pin on each side — unless some inventor can furnish us 
a stud with a slot instead of a round hole for the hair spring. It 
has been proposed to make a square steel punch, and hammer 
the stud upon it till the hole becomes square. If this plan is 
to be followed, however, it would be sufficient to have the 
punch square on one side only, leaving the other side of the 
hole round, as usual, for the pin. 

(282.) The spring must be pinned perfectly solid, both in 
the stud and the collet, so that not the slightest change or 
yielding can occur. The larger end of the pin should be 
towards the body of the spring and should not projectat all out- 
side of the stud, so that under no circumstances can it affect 
the action of the spring, as it would do if it extended alongside 
of it even for a short distance. Enough spare spring must be 
left, when broken off, to have at least one-eighth to one-quarter 
of an inch beyond the stud, after the watch is regulated, to 
provide for future contingencies requiring it to be let out. 

(283.) The Regulator. — A few words about the regulator are 
necessary, since even its purpose does not seem to be always 
comprehended. If we could make the ideal perfect regulator, 
it would be in effect a movable stud, which would allow of be- 
ing shifted in either direction as the exigencies of the timing 
should require, but would then become the end of the working 
portion of the spring, holding it as firmly as the real stud does, 
and cutting off the part behind it from any influence upon the 
time of the watch. But since this cannot be practically real- 
ized — at least, it has not been done, so far as I know — we 
should come as near to this ideal as we can, by placing the reg- 
ulator pins as closely together as possible, without binding on 
the spring when the regulator is shifted. The most perfect re- 
sults in time are obtained when the regulator stands pretty well 
back towards the "slow," i.e.., near the stud — and, in fitting in 



THE WATCH ADJUSTER'S MANUAL, 121 

a spring, if it does not give the correct number of vibrations 
with the regulator standing between the middle of its scale and 
the stud, the spring should be drawn further through the stud 
to shorten it, rather than move the regulator further towards 
the "fast." 

(284.) Positiofi of the regulator pins. — It may happen that the 
regulator pins are further from or nearer to the balance-jewel 
hole than the hole in the stud, and this should be looked into. 
If it was so, before the spring was fitted, it should have been 
looked to then. Sometimes, in putting the watch together, the 
regulator cap or center-piece gets screwed on the wrong way 
and causes the pins to stand further in than they should. If 
this is the cause of the trouble, reversing the cap will throw 
the regulator further out and obviate the need of bending the 
spring. Perhaps the regulator-pins can be bent out (or in, as 
required,) to reach the circle of the spring, and then be ??iade 
perpendicular where the spring coil touches them. But if not, 
the spring must be bent near the stud to bring the outer coil within 
the circle of the pins as soon as possible, as, throughout the 
sweep of the regulator, the spring must \\q freely between the 
pins, not pressing against either of them, when the balance 
is at rest. If there is considerable space between the pins, 
the spring should stand in the center of it. This position of the 
spring should be tested by screwing down the balance-bridge in 
its place and moving the regulator each way. If the spring 
must be bent, the bend should not be too abrupt at the point 
where the outer coil is made to become concentric with the reg- 
ulator, but should be made far enough from the stud so that the 
change of direction it produces in the spring at that point will 
not be more than about 15°, — never over 25°. 

Such an error is proof that there has been some mistake made 
either in the manufacture of the watch, or in subsequently fit- 
ting a regulator in it. The foregoing course will answer for 
ordinary work. In a fine watch, you should alter either the 
regulator or the stud, to avoid bending the spring. Which 
should be changed, may be judged by trying on it a suitable 
spring having the proper number of coils, and observing the 
space it requires, and whether it best fits to the stud or to the 
regulator. 

(285.) Testing the freedo?n of the spring. — When it is correct, 
take the balance-bridge off, and lay it bottom upwards; having 
taken the stud out of its hole, place the pivot of the balance in 
its jewel, and hold the staff nearly upright with the tweezers. 
Then the spring should lie naturally in the regulator-pins, while 



122 THE WATCH ADJUSTER'S MANUAL. 

the stud must hang freely directly over its hole and must point 
straight down into it, which will show that the spring is prop- 
erly pinned and correctly shaped. If it is not as described, it 
must be made so, for the spring must have exactly the same 
form when loose as when it is secured in the watch for running, 
so that it may stand perfectly free from any twist or constraint 
during its vibrations. This is indispensable to its good perfor- 
mance. When the stud is a heavy bar, the above test cannot 
be applied, and, instead of that, the collet should be removed 
from the staff, and the bar screwed into its place, when the col- 
let should naturally come exactly concentric, with the balance 
pivot-hole. If not, the spring should be bent to bring it so. 
We often see springs that are too large, with one side spread 
out, while the other is compressed within narrow limits. Also, 
springs twisted sideways at the stud, to go over or under a 
center wheel, and many similar makeshifts. Such jobs may 
be excusable when the owners will not pay a price for which the 
watchmaker can afford to do the work properly, but they 
should be given to understand that good service cannot be ex- 
pected from them. 

(286.) Taking out the stud. — In taking out the stud we often 
see workmen use a knife to pry it up, and, if it should come up 
more easily than was expected, the knife-blade suddenly slips 
across the bridge, and off goes the pivot. Tweezers have been 
made for pushing out studs — also pliers for the same purpose. 
But as good a way as any is to rest the arm of the bridge upon 
any convenient square-edged block of metal, say an inch thick, 
to allow the balance to hang down from the stud, or rest par- 
___^ tially on the bench, while you push the stud out 

^^ ) from above with a pin-punch of suitable size. As 

the end of the arm is supported by the top of the 
block, close up to the stud, which is in contact 
with its side, it is very easy to hold the bridge 
level under any amount of force required for push- 
ing out the stud, without the slightest risk to any part. In 
Fig. 20, a is the block; ^, the arm of the balance-bridge, and 
^, the stud. 

(287.) Putting in beat. — Putting the watch in beat is an 
operation that frequently troubles beginners, and sometimes 
those who are very far from being beginners. I will therefore 
give directions for so much as relates to the hair spring. 
Errors in the escapement, etc., will be treated in their proper 
places. When the power of the movement is cut off and the 
balance at rest, the position of the parts should be as follows: — 



a 



Fig. 



THE WATCH ADJUSTER'S MANUAL. 123 

In the chronometer, the unlocking jewel should stand just on 
the outside of the unlocking spring, i.e.^ not on the same side 
as the escape-wheel, or the unlocking side, but on the opposite 
side. See Chapter XXVIII. In the duplex, the slot in the 
roller-jewel on the staff should be between the point of the 
locking tooth resting against it and the line of centers. See 
Chapter XXVI for full information about the duplex. In the 
detached lever watch, the ruby pin should be in a line between 
the centers of the balance-staff and lever-staff, /.<?., on the line 
of centers. When the hair-spring stud is fixed to the balance- 
bridge, turn the regulator so that it will point to the lever-staff, 
while the bridge is screwed in its place in the watch, and you 
can use the regulator as a guide when the bridge is taken off 
and turned over. Then the ruby pin is easily put in line with 
the regulator while the balance-bridge is lying bottom upwards 
on the bench and the balance-pivot in its hole, and got very 
close before the spring is put into the watch at all. Then it 
can be tested by "sighting," or by placing a blunt screw-driver 
against the fourth wheel, or the one which carries the seconds- 
hand, and moving it very slowly so that the balance will vibrate 
as far in each direction as the lever carries it, but no further. 
Notice the position of the arm, or a screw in the rim, at each 
extreme, then turn the collet so as to cause it to stand at a 
point midway between them when at rest, and it will be in 
beat. 

(288.) Inthe horizo7ital or cylinder escapement^ the stud should 
be in line with the two impulse lips of the cylinder. But if the 
mechanism is not in its normal condition, and the watch does 
not prove to be in beat, upon trial, take your oiling-wire or a 
stiff bristle and with it move the balance very slowly each way 
till the escape-wheel tooth drops, but no further, noticing the 
position of the banking-pin on the rim, at each drop. Then 
place the pin halfway between these two drop-points, and hold 
the balance there while you " sight" a line through the center 
of the stud to the cylinder-pivot, and identify the point on the 
rim of the balance which is in that line, by means of some mark 
or stain, etc., or its distance from one of the arms, or in any 
other way. Then take off the bridge, remove from it the bal- 
ance and stud, and turn the collet so that the stud will hang 
naturally in that line from the mark on the rim to the cylinder 
pivot, when the balance is held horizontally (385), and the 
watch will be in beat when put together, provided the spring is 
not forced out of its normal shape when the stud is fastened in 
its place. Full instructions for getting each kind of escape- 



124 THE WATCH ADJUSTER' S MANUAL. 

ment in beat are given in the Chapter devoted to each one in 
Part Fifth. 

(289.) Turning the collet. — Most workmen use a screw-driver 
or a knife-blade to shove the collet around with, and unless 
they move it very carefully it will slip off and "jab" into the 
spring; or it will pry open the cut and loosen the collet, render- 
ing the watch liable to be thrown out of beat by jars, or even 
by running, making it unreliable for time and likely to stop. 
A tool can be made in a few minutes which will turn the collet 
without trouble or danger. Take a thin piece of steel, say a 
J. piece of the mainspring of an English lever watch, one- 
/{x eighth of an inch broad, and hollow out the end into 
\ / two claws or prongs — a long one on one side, and a 
) ( short one on the other, as shown in Fig. 21. The latter 
■■ should point towards the end of the former, and be so 
formed as to hook into the cut in the collet, while the 
former rests against the side of the collet. It is used by plac- 
ing it flatwise on the spring, pressing it lightly against the 
collet, Siud pulling^ not pushing, with the short claw in the cut. 
Mount it in a light handle, and keep the short claw in a good 
condition and a little under-cut. 

The collet can be easily raised or removed by a small tool 
made of thin flat sheet steel, shaped like a very tapering screw- 
driver, with a slot filed in the center to receive the balance-staff. 
This tool being secured in a handle, the thin edge is inserted 
under the collet and pressed in, and moved to and fro sideways 
till the collet is lifted sufiiciently. 

The remaining portion of the fitting of hair springs is given 
in the next chapter. 



CHAPTER XIX. 

On Poising. 

(290.) Poising the collet. — After the watch is put in beat and 
is fitted for running, we must know if the balance (with collet 
and spring) is perfectly in poise, for if it is heavier on one side 
it can never give reliable time. The poise cannot be finally 
tested until now, with most watches, because they generally 
have an open cut in one side of- the coHet, making it lighter on 
that side; and it would be useless to finish the poise till the po- 
sition of that cut had been fixed, as any turning of the collet 
for the purpose of putting the watch in beat would bring the cut 
into a different position and throw the balance out of poise 



THE WATCH ADJUSTER'S MANUAL. 125 

again unless the collet itself has been poised. In good watches 
that should be done, as is done with chronometers. After the 
balance is perfectly poised, put on the collet, with the pin in its 
hole and also a piece of hair spring long enough to project -^^ 
inch out of the pin hole. If not in poise, file off the heavy side 
enough to make it so. A collet with a very wide cut should not 
be allowed in a fine watch, but rejected and a new one made 
with the cut closed. 

(291.) Poising the balance. — If the balance has movable screws 
in its rim, the perfecting of the poise may be done by drawing 
out one of these screws a little. If much correction is needed, 
two or more screws should be drawn, so that their position 
would be altered but little, and nearly alike. But this mode 
of correcting the poise is not allowable with a cut balance, 
which is adjusted for heat and cold, but only for uncut or unad- 
justed balances, in cheap watches. 

In a compensation balance there are generally four screws 
called "quarter-screws," or mean-time screws, which may be 
moved to perfect the poise, one at each end of the center-bar, 
and another pair midway between them on the rim. But the 
latter pair should only be moved very slightly, as it is likely to 
disturb the compensation for heat and cold ; while the former 
pair will affect only the rate, and even this may be avoided by 
moving both screws to poise the balance, — one of them in, and 
the opposite one out, which of course maintains the 77iea?i dis- 
tance of the two from the center of the balance the same as it 
was before, and does not affect the rate. See also (346). Plain 
balances are poised by filing away metal on the heavy side or 
adding weight on the light side, as by tinning:, etc., (332, zzi)- 

(292.) It is, of course, desirable that the balance should be 
in poise before the spring is put on, as that facilitates the final 
poising. Besides that, the parts then on the staff are consid- 
ered fixed and permanent, but the collet and spring are mova- 
ble; therefore the fixed parts, as a whole, should be poised, 
and then the movable parts prevented from destroying that 
poise. Inasmuch as our object is to get the balance in poise 
while running, it must be plain that it should be in poise with 
everything on it exactly as it will be when running. That is, the 
roller table, the hair spring and the collet, and all other parts 
should be on the staff; and if the collet or any other piece is 
not perfectly poised in itself, its final position must be deter- 
mined before the poising is finished. In chronometers it is 
common to drill a hole in the roller-table, opposite the impulse 
jewel and notch, to make up for the metal there cut out and 



126 THE WATCH ADJUSTER'S MANUAL. 

balance its weight; and a similar course would be desirable in 
fine lever watches, not only with the rollers, but also with the 
collet, as described in the preceding section. 

(293.) Poising the hair spring. — By poising the collet in the 
manner stated, w^ith a short piece of spring in the hole with the 
pin, as the hair spring will finally be, we get everything in 
poise except the hair spring itself. That cannot be poised with 
certainty. When the spring is finally pinned in the collet, we 
can tell whether it is approximately in poise by its concen- 
tricity. It is impossible to tell precisely how much of the outer 
coil or coils is supported by the stud. It may be just enough 
for the remainder of the spring, the weight of which is sup- 
ported by the balance axis, to be just in poise — or it may be 
more, or less, according to the manner of pinning in the stud. 
The best we can do, therefore, is to poise everything that is 
rigid and can be poised with certainty, (290 to 292), then get 
the spring pinned co7icentric, as accurately as possible, when on 
the balance staff. Further observations on this point will be 
found in sections (294) to (297). 

(294.) Rule for poising the flat spiral. — If the balance and the 
collet have been poised, (290, 292), and the hair spring fitted 
on as previously described, evenly and truly coiled and concen- 
tric with the balance, (277), and the inner end of the spiral 
reaches to the elbow at the pin, it will be unnecessary to do any 
more — in fact, very little more can be done with any certainty. 
But in fine watches, if the inner part of the spring is more open 
at the collet than directed, the collet should be poised with a 
piece of spring pinned in, corresponding in length, shape and 
weight, to all that portion of the spring (at the inner end) which 
deviates from the true spiral form. Examine the spring to find 
where it begins to deviate from the spiral form, towards the 
collet, and from that point to the end in the collet is the portion 
which should be poised with the collet, by pinning in a piece of 
spring as near like it as possible, correcting the poise by filing 
the collet (290.) It is then supposed that the truly spiral por- 
tion of the spring will, by itself, be practically in poise. Some 
workmen merely poise with the spring finally pinned in the 
collet, and call it right if an allowance for the waste end beyond 
the stud will make it in poise. But most workmen are content 
to poise the balance, then the collet, and fit the spring on con- 
centrically without poising it at all. 

(295.) Difficulty of poisi?ig the hair spring. — In Fig. 22 we have 
one coil of a spiral A^ compared with a circle which coincides 
with the middle point of the spiral at d. The ends a and b are 



THE WATCH ADJUSTER'S MANUAL. 



127 



equally distant from the circle, and if we should poise it in the 
position shown it would be nearly in poise, because a is as 
much nearer the center as b is further from it ; but the outer side, 
e, b, would be slightly the heavier, and with 
^ ^ it would overbalance the part c d e. If 
we poise it with the dab vertical, the outer 
half, d e b^ will still further overbalance 
a c d, because the former is longer and also 
further from the center. It is evident, there- 
fore, that the outer half of every coil will 
slightly overbalance the inner one. A spiral 
spring is composed of a number of such coils. 
If the spring is pinned in even turns, as B^ in Fig. 23, the 
lower halves of all the coils will be heavier than the upper. 
If there is a fractional part of a coil, as C, in Fig. 24, the frac- 




FlG. 22. 





Fig. 23. 



Fig. 24. 



tional part, (from the stud to/,) will overbalance the outer 
halves of the complete coils. 

(296,) Disturbing effect of the stud. — But even if it were pos- 
sible to make any reliable calculations of the poise of the spring 
by its coils, the action of the stud would render them valueless. 
In Fig. 25, we have a spiral properly pinned in the stud and 
collet, a being the stud, and b the regulator pins. Now, how 
much of the spring is supported by the stud, and how much 
rests on the balance pivots, in the position shown? If the 
spring stands perfectly concentric and free at the center, more 
of the spring will rest on the pivots when the point ^ or ^ is 
uppermost than when ^ or ^ is at the top, because the spring 
yields more easily when the curve is opening or straightening 
than when closing. This shows that even if we could get the 
spring perfectly poised in one position, it would not be in poise 
when in a different position. So far as concerns the poise, the 
outer end of the spring is virtually at the point where the stud 
ceases to support the coil. And as that point is constantly shift- 



128 THE WATCH ADJUSTER'S MANUAL. 

ing, we never can tell where the virtual end is, nor which half 
of the coils is the outer half, nor whether we ought to poise for 
complete coils or for a part of a coil. 

(297.) Effect of excejitric sprmg. — But as the spring is seldom 
pinned so perfectly that it is truly concentric, but is generally 




Fig. 25. 

sprung to one side, that causes still greater variation and un- 
certainty, for the stud may in such cases support anywhere 
from one to half a dozen coils. The poise is not only uncer- 
tain, but its effect is so much smaller than that of the side pres- 
sure on the pivots as to be of comparatively small consequence. 
In watches, the weight of the spring is so trifling, and so near 
the balance axis, that, if the spring is pinned concentrically in 
the collet, (277), there cannot be a poise-error of any conse- 
quence in the spring, and if there is any such error found by 
timing, we may conclude that it arises from the spring not be- 
ing pinned concentrically at its outer end, and not from imper- 
fect /m^ of the spring. These explanations will show the cor- 
rectness of the statement in section (294) that, if the spring is 
properly fitted in as there described, it is not only useless but 
impossible to poise it any further. 

(298.) Poising the Breguet spring. — All that can be done is to 
have the balance, and then the collet, in poise, so that the col- 
lel can be turned in any position without disturbing the poise. 



THE WATCH ADJUSTER'S MANUAL. 129 

Whether it will then be in poise when running will depend on 
how much of the spring is supported by the stud, and can only 
be told, if it can be told at all, by testing it while running, as 
in section (302). 

(299 ). Poising the cylindrical spring. — The balance should first 
be poised with all its fixed parts in their proper positions, (or, 
what is better, with each roller separately poised,) but without 
the collet bar. Then the spring, with its inner terminal curve 
formed, (but before the other curve is bent up,) is properly 
pinned in the collet, and poised to see if the body of the spring 
is concentric with the balance. In doing this, if the spring is 
not in even coils, i.e.^ if there is a fractional part of a coil, 
counting from the collet end, there should be a preponderance 
of weight on the side where the outer end is, corresponding to 
so much of the spring as exceeds the complete coils. This al- 
lowance is judged as to its correctness by the judgment of the 
experienced workman, or is tested by hanging an equal length 
of similar spring wire on the opposite arm of the balance and 
at an equal distance from the center. If that does not bal- 
ance it, the body of the spring is probably not concentric with 
the balance axis, and should be changed by bending at the collet 
end or curve, till correct. Some workmen merely poise with a 
duplicate of the inner terminal curve pinned in the collet bar, 
as for the flat spring (294), making the correction by filing the 
collet, and get the body of the spring concentric by eye, by 
whirling the balance in the calipers or turns. In either case 
the final test is by running it in positions (302). It is gener- 
ally supposed that, if the terminal curves are properly formed, 
the center of gravity of the entire spring will be on the balance 
axis when running. But that is an error. Springs with termi- 
nals require poising as much as any others. 

(300.) Poising tools. — There are two kinds of poising tools, 
the notch and the straight-edge. It is best to do the main por- 
tion of the poising upon the notch tool, using the straight- 
edge for the final tests only, as much time will be saved thereby. 
The poising tool consists simply of two jaws or pieces of hard 
metal, whose distance apart can be changed to suit the length 
of the piece being poised. By making suitable notches in a 
straight-edge tool, you have both kinds in one. The jaws may 
be of either brass or steel, with the edges perfectly straight, 
smooth, polished and thin, like two knife blades, parallel to 
each other and with the edges upwards. At each end of the jaws 
may be made a pair of notches — one pair fine, the other larger. 
The notch should be about the depth and a little wider than 
9 



130 THE WATCH ADJUSTER'S MANUAL. 

any pivot that is to go in it, the bottom semi-circular in form, 
and the edges filed very thin so as to present almost a knife 
edge to the pivot, and must be kept clean and polished. 

(301.) The staff should be so placed in the notches that they 
will not rub on the shoulders of the pivots. If the balance 
seems to be correct and does not turn of itself, whirl it with a 
bristle, and if it stops with all sides up, indifferently, it may be 
placed on the straight edges, which should be levelled and 
made horizontal so that there will be no tendency for it to roll. 
It is not necessary to whirl the balance here, but simply place 
it with different sides up, and if it shows no disposition to 
change its position it is in poise, for there is no friction on the 
pivots to prevent it rolling over if there was the slightest ten- 
dency to do so. Whirling the balance will inevitably cause one 
or the other of the shoulders to bring up against the jaws, and 
necessitate another test. But a well fitted notch leaves little to 
be desired, or accomplished by the straight edges. 

(302.) Testing the poise. — The poise may be tested after the 
watch is running, by timing it for 3 or 6 hours each in the four 
vertical positions, viz.^ with figures XII and VI, III and IX al- 
ternately upwards, and if the times are the same in the different 
positions, the balance is supposed to be in poise. Rules for 
correcting the poise will be given in the Chapter on Adjusting 
for Positions. But if the foregoing directions are carefully 
followed, we may safely say that any error of poise will not be 
due to the spring. But in order that this test should be trust- 
worthy it is necessary that the balance jewel holes be well 
fitted to the pivots, the escapement in perfect order, and the 
lever poised, so that there may be equal friction in each posi- 
tion; and the watch must be wound up an equal distance for 
each test, so that the motive force may be the same in each 
position. Otherv/ise, errors due to unequal friction or action, 
imperfect fitting, or lack of isochronism in the spring, maybe 
erroneously ascribed to want of poise in the balance. 

(303.) Oiling the escapement. — When everything is done, so 
that you are sure you will not have to take the balance out 
again, a little oil should be put to the jewel holes, they and the 
pivots being, of course, perfectly clean. Put in barely enough 
oil to fill the holes but not stand at all in the oil-cup or concavity 
of the jewels. If it seems to be soon drawn away by capillary 
attraction between the hole-jewel and the end-stone, put in a 
little more. But put no oil on the pallets of a verge; a very 
little only on the long impulse-lip and the escape-wheel teeth of 
a cylinder; a very little on the pallets of a lever watch, but 



THE WATCH ADJUSTER'S MANUAL. 131 

none on the ruby pin nor in the notch of the lever; a little on 
the roller-jewel of a duplex staff, but none on the impulse pal- 
let; none on either the unlocking- or impulse-jewels of a chron- 
ometer, none on the detent-pallet, and but little on the bal- 
ance-pivots. Use none but the very best watch-oil to be had 
at any price. Keep the bottle closed and in the dark; keep 
your oil-cup perfectly clean and covered; put but little oil in it 
at a time, and fill it often with fresh, wiping it perfectly dry 
and clean with paper every time you fill it. Make an oiling- 
wire by taking the temper out of a sewing-needle, file it taper- 
ing to a point as fine as a hair, then turn over the extreme end, 
and make the smallest possible loop or ring, so close that you 
can see no hole in the center, and mount it in a light handle. 
This loop will take up all the oil that any ordinary hole ought 
to have. Keep it away from soldering fluid, water or dirt, and 
keep it out of your mouth. Of course, if the balance, spring, 
etc., are at all greasy or dirty, they should have previously 
been hung on a wire hook and moved about in a bottle of ben- 
zine for a few seconds, then dried by exposure to the air. 

(304.) Regulating the watch. — The spring being properly fitted, 
everything poised, in beat and oiled, nothing remains but regu- 
lating, unless the spring is to be adjusted for isochronism. Full 
instructions for timing the watch quickly are given in Chapter 
XX; for regulating generally in Chapters XXI and XXII, and 
for fine timing or rating in Chapter XXIII. The isochronal 
adjustment of the spring is treated in Part Sixth. Although 
I have dwelt upon a large number of details, the workman should 
remember that it will take but little more time to do his work 
rightly, if he understands how it ought to be — and it has been 
the object of these explanations to clearly show the proper 
method, so that when his work is done it will be correctly done. 



CHAPTER XX. 

Quick Ways of Bringing a Spring to Time. 

(305.) By comparison of balances. — Take as the standard a 
movement giving the same number of vibrations as required 
for your trial watch, and which is very closely regulated. Ar- 
range it in a movement box or otherwise so that its balance 
can be plainly seen. Start the balance of the trial watch to 
vibrating synchronously with the timing balance, i.e., starting 
at the same instant and in the same direction. Watch them 



132 THE WATCH ADJUSTER' S MANUAL, 

closely, and, as soon as the trial balance perceptibly gains on 
the other or falls behind, you move the regulator of your watch 
to correct that error, and start again. Do this till your balance 
does not vary perceptibly in one minute, and it is regulated 
within about one minute per day. If it does not vary percep- 
tibly in five minutes, it will run within 15 or 20 seconds per day. 
Of course, it is not necessary to watch it all the while, but 
merely look at it occasionally, to detect the slightest varia- 
tion. You could be regulating a number of watches at the 
same time. This is the quickest method known for regulating 
a watch in a few minutes. 

(306.) By opposition of balances. — Some are not quick enough 
to follow the foregoing method with certainty, and they should 
wait till the two balances get in opposite phases of the vibra- 
tion, i.e.^ one will be moving at its greatest speed while the 
other comes to rest and begins its return vibration. If this can 
be clearly seen, so as to know that each balance stops just at 
the middle of the vibration of the other, this variation will 
mean a gain or loss of half a vibration on the other balance. 
If you know how long the time is since the start, say one min- 
ute, that would be varying -^^ second per minute, in an 18,000 
train, and would show you how much to move the regulator. 
But it is not necessary to know the time. You only need to 
know positively whether the trial balance gains or loses, and 
that shows how to move the regulator. 

(307.) By reversal or coincidence of balafices.- — If you do not find 
it easy to decide when the balances are in opposite phases, you 
can wait till they move in opposite directions, which means that 
the trial balance has either gained or lost one vibration on the 
other. This is easy to see, in most cases; if not, let it go 
a while longer till it vibrates in the same direction and starts at 
the same time as the timing balance, which indicates a gain or 
loss of two vibrations, or | second, in an 18,000 movement. 
These methods do not require any counting or observation of 
time, although the process of regulating would be made more 
definite and certain by observing the length of time the trial 
has lasted. But even that does not require to be done so 
closely as is necessary by other methods of regulating. 

(308.) Long trial by co??iparison of balances. — When you have 
your watch so closely regulated that there is no perceptible differ- 
ence between the balances, you can make a long trial, by starting 
your watch exactly with the other, then hang it up, examining 
it, say, every ten minutes, till you see a variation. Turn the 
regulator to suit, start again, and try it for an hour. If your 



THE WATCH ADJUSTER'S MANUAL. 133 

balance has only gained or lost perceptibly (305) in an hour, 
(say, J of a vibration,) that would be only about one second 
per day. In this way, or even by one of the other methods 
described, you can regulate a watch closely in a few minutes, 
while being also engaged in other work, merely watching it 
enough to see when the vibrations are in opposition or reversed. 

(309.) Regulating to a fraction of a second per day. — In rating 
a fine watch, this method gives the closest results of any that 
can be followed outside of a well-equipped observatory. After 
getting your watch so closely regulated that you can see no 
difference between the tw^o balances after running it for an 
hour, as described in the preceding section, you try it for a day 
in the same manner. For the sake of being sure that you are 
right, you compare the balances every two hours during the 
first half of the day, and if, at the end of the twelve hours, 
you can see no perceptible difference between them, you con- 
tinue the trial over night. In the morning, you first compare 
their seconds-hands, to be certain that both watches are still giv- 
ing the same vibration, i.e.^ if both of them pass a division on 
the dial at the same time. If your watch was a beat or two 
before or behind the division mark when the other was just on 
it, yours has of course gained or lost so many beats. But if 
both strike the mark at the same instant, and their jumps or 
movements exactly coincide, you will know that they only 
differ by a part of a vibration. You then compare the balances, 
to find what the difference between them is, and whether your 
trial watch is ahead or behind. If the balances are in opposi- 
tion, i.e.^ one is reversing while the other is in full motion, the 
difference is half a vibration, or, in an 18,000 train, -^-^ second 
for the 24 hours since the trial began. If more, or less, you 
can tell what it is by sections (305) to (307). Also, see sections 
(215) to (222). Of course, you require a very accurate timing 
watch for such regulating. A box chronometer specially ad- 
justed to positions, with a glass over the movement, would be 
better yet. But if you have a first class timepiece to compare 
with, there is no difficulty whatever in following this method, 
except that you must be quick-witted in comparing the bal- 
ances. 

(310.) By counting the vibrations by ear. — This is the quick 
method usually followed, and may be adopted by those who 
cannot well use the preceding methods. When the watch is 
cased, hold it to the ear with the left hand, having the pencil 
in the right. After getting the ear well accustomed to t/ie 
period ol the ticks, begin counting them as the regulator sec- 



134 THE WATCH ADJUSTER'S MANUAL. 

onds-hand touches 60, marking down every 10 beats, till tne 
end of the minute. If there were more (or less) than the 
proper number of beats given, move the regulator to slow (or 
fast), and try it for another minute — and so on till you get the 
right number. Then you can keep on counting for 2, 3, or 5 
minutes, if you wish to get it very close, immediately. One 
beat in 5 minutes would (in an 18,000 train) be 12 seconds in 
5 hours, or about one minute per day. Instead of the regula- 
tor, the seconds-hand of a box chronometer or good watch will 
answer. 

(311.) Same J if movement is not cased. — The easiest way is to 
get the image of the regulator seconds-dial in a mirror before 
you, (see Chapter XII, sections (172 to 174),) so that you can 
keep both it and your trial balance in the eye, count the vibra- 
tions as before, and proceed as there directed. By getting the 
period of the vibrations well in mind, and especially by nod- 
ding the head in unison with them, you can look at the image 
of the seconds-dial long enough to know the exact beginning 
and end of the minute without losing the run of the vibrations. 
Both the nodding and the counting aloud greatly assist in keep- 
ing track of the vibrations and the number. The reader will 
do well to frequently consult the Chapters on counting vibra- 
tions, to find points which he can adopt with advantage. By 
either of the above methods he should remember that a chronom- 
eter gives only one tick to two vibrations, and he should double 
the number of beats counted to get the number of vibrations. 
He can perhaps think of some combinations of the methods 
given, which might be specially convenient for him — say, by 
the use of a vibration marker, mirrors, counting backwards, etc., 
with parts of the above, i.e.^ using a part of one method and 
another part from another method, to make up a complete 
working method. That is not necessary, however, as some of 
the methods given are sure to meet any case that can come up. 



CHAPTER XXI. 

Regulating Watches. 

(312.) Regulatings as distinguished frofn ratifig or timing. — 
Strictly speaking, regulating would come under the head of 
timing; but practically, regulating is the coarser branch of the 
work. It has no reference to any trials for or tests of isochron- 
ism, positions or compensation, but consists merely in moving 



THE WA TCH ADJUSTER'S MANUAL. 135 

the regulator or changing the length or strength of the hair 
spring to bring the watch to time under ordinary conditions of 
usage. Anything which varies to exceed half a minute per 
day is not being rated, but regulated. It is not in fit condition 
to be rated. The term regulating also applies to watches which 
have been cleaned and repaired, but nothing has been done 
connected with the adjustments. 

(313.) Another and perhaps plainer distinction is this: We 
may call it regulating when it is not necessary to go by sec- 
onds, but is sufficiently close if we only need to set the watch 
by its minute-hand. Thus defined, this Chapter will apply to 
all ordinary watch repairing, including at least nine-tenths of 
the hair springs and other jobs done by the trade. Conse- 
quently, while not a part of the adjustments, it is a part of the 
springer's work, and therefore entitled to an honorable place 
in the Manual, since the adjustments cannot be made satisfac- 
torily till after the points included in this chapter have been 
conscientiously attended to. Although not fine work, it is very 
essential and important, and the reputation of the watchmaker 
in the community depends far more upon his skill and thorough- 
ness in regulating than in adjusting. It will be for his advan- 
tage to bring his regulating as near to being adjusting as he 
can afford to do, and to habitually employ as many of the methods 
and means used in the adjustments as can be easily adapted for 
the purposes of regulating. With this principle in view, I have 
included in this chapter several points — particularly those on 
regulating Breguet springs — which would ordinarily be treated / 
under the head of Rating. 

(314.) Put everything as it was before. — Regulating a fine 
watch is an operation which but few workmen are capable of 
doing properly, or, indeed, without injuring it. And even with 
the cheaper grades of time-pieces, there is more in it than many 
suppose. When a watch is merely cleaned, or the repairing of 
it does not require any alteration of the hair spring, the great- 
est care should be taken, especially with fine work, that it be 
put together precisely as it was before. The regulator should 
be at the same place, and the hair spring should occupy the 
same position between the regulator pins, as before it was taken 
down. To insure this, a careful examination should have been 
made, with the balance at rest, free from the motive force of 
the mainspring, and the position of both the regulator and 
hair spring noted down — for in a fine watch both of them have 
probably been carefully adjusted, and changing either of them 
or opening or closing the regulator pins might seriously damage 



136 THE WATCH ADJUSTER' S MANUAL. 

the adjustment. Even in cheap watches, following this rule 
will frequently save several days in bringing them to time. 
Also, count the number of vibrations per minute and note it 
down. If the number is correct, it will assist you in regulating; 
if not correct, i.e.^ not the number the train was designed to 
give, (Chapter XIV,) it will put you on track of some fault that 
should be remedied. 

(315.) P re-requisites of the tii7ii7ig. — But if a watch does not 
perform satisfactorily on trial, or if the workman is sure from 
inspection that it will not do so, the defective conditions must 
of course be changed and corrected. I have already stated 
how the hair spring should be pinned in the collet (273 to 277), 
and stud (282) ; that it should be perfectly free from constraint 
when fastened in the movement, (285) ; that the outer coil 
should stand perfectly free between the regulator pins as they 
are moved through the whole of their sweep from " slow" to 
"fast," not moving nearer to or against either pin at any point 
in the sweep ; and that the regulator should stand pretty well 
back towards the " slow" when the watch is regulated. The 
pins should both be tight in their places, so that they cannot 
yield any when the spring presses against them. If one of 
them has a foot to close the bottom of the opening between 
them, the spring should be entirely free from it, nor should any 
dirt be allowed to accumulate there and touch the spring. 

(316.) The regulator. — As a general rule, the regulator pins 
should be as close together as possible and. yet leave the spring 
free between them, (586). But if they are found otherwise, 
they should not be closed without good reason, for they may 
have been so opened for a purpose, by some one who fully un- 
derstood the effects of so doing. But wide pins may justly be 
regarded with suspicion. The effect of having the pins very 
open is not only to render the spring less susceptible to control 
by the regulator, but also to cause sudden and violent checks 
to its motion, making uniform progression of force difficult, if 
not impossible. Moreover, the spring vibrates upon the pin 
against which it rests, as a fulcrum or pivot, moving in one 
direction on one side of the pin, while back of it it yields in the 
opposite direction. Sometimes the spring will even slide along 
the pin with every vibration. In either case, an irregularity 
of motion results which is injurious to its proper action, and 
should be avoided whenever the position of the regulator pins 
comes within the scope of the repairer's duty. 

(317.) Time of winding. — Many watchmakers do their winding 
and regulating at night. This is all right for watches known 



THE WA TCH ADJUSTER'S MANUAL. 137 

to be in perfect order, and therefore needing nothing but regu- 
lation. But for custom watches, the preference is to do it the 
first thing in the morning, so that if any alterations or examin- 
ations are needed they can be made at once. If a watch is 
found still, or acting strangely, at night, it may start on before 
morning, and every workman knows that the best time to exam- 
ine into any trouble is while that trouble is yet in operation 
and can be seen, but it may escape notice or require a long 
search if allowed to pass on. Besides, this work is a good 
preparation for the more serious labors of the day. No one 
feels like sitting down to the bench in the morning and plung- 
ing right into some delicate job the first thing, but after wind- 
ing he is ready to take hold of anything that is waiting for 
him. Use always solid-pipe, well-fitting bench keys for wind- 
ing. Careless workmen ruin more winding-posts and bend 
more teeth by not following this rule than their heads are 
worth. When winding, turn the key, but hold the watch still. 
Many persons twist the watch as much as they do the key, at 
the risk of overbanking, breaking off the ruby pin, stoppage, 
etc. 

(318.) Proper order in regulating. — In regulating, there is a 
certain order to be followed. Workmen often find watches 
stopped, and after cautious examination and perhaps much loss 
of time, discover that they had forgotten to wind them; or they 
find a watch more out of the way after regulating than before, 
and cannot tell whether they had set it or not, after turning the 
regulator; or they will wind and set, but forget to regulate it. 
The proper way is first to change the regulator, the hands re- 
maining as they were, so that no mistake can be made about 
the correct change required. If you should forget, or be called 
away for a moment, the hands are still as they were, so that 
you can see what the error was. Next wind the watch, lastly 
set it. After winding always give the watch a little shake, or 
be sure that it is going, as cheap watches often stop from wind- 
ing or turning the hands backwards, etc. After winding all 
your watches glance over them, and if every one is properly set 
to time, you may be sure that they are also regulated and 
wound. Otherwise, you cannot be certain. By following the 
above rules invariably^ you will never have any doubts or mis- 
takes. In regulating fine watches, either keep a memorandum 
book, or attach a tag to each, and note down the error and the 
date, thus: "Aug. 10, 45 s. fast," "Aug. 12, 52 s. fast, Reg. 
and Set." Or the foregoing can be abbreviated into "12. 52 
s.f., R. S. " In this way you will know how long a time the 



138 THE WATCH ADJUSTER'S MANUAL. 

watch has been in making the error, and what effect your pre- 
vious alterations had; also whether the rate was regular or 
varied. Always turn the regulator too little rather than too 
much, and in fine alterations use the eye-glass to observe the 
amount of movement it has received, especially if it has a ten- 
dency to spring back. For further instructions see Chapter 
XXIII, on Rating. 

(319.) In setting the ha7ids of a lever or cylinder, if they do not 
turn hard and the movement is in good condition, they may be 
moved either forward or backward, — the way which will require 
the least turning. But if they move at all hard, and the lever 
is short, they should be turned forward only, or the balance 
pivots may be bent or broken, or the watch stopped. Chronom- 
eters and duplex watches should commonly be turned forward 
only. (See Chapter XXII, sections (341) to (343). Repeaters, 
alarm watches, and all complicated movements should always 
be turned forward, by the customer, and by the workman also, 
unless he is perfectly familiar with the requirements of the 
movement in hand. If the hands move quite hard, they should 
not be turned at all, as damage is almost sure to be done, but 
the difficulty should be ascertained and remedied immediately. 
See Chapter II. All of the foregoing and any other defective 
points in the movement should have been examined while tak- 
ing it apart, and all repairs made either at once or at least be- 
fore cleaning. But I have mentioned them here, because they 
are among the pre-requisites of the timing. 

(320.) Setting to seconds. — In setting your watch to seconds, 
do it by stopping the balance. I have seen those who claimed 
to be fine workmen twisting the seconds-hand forwards and 
backwards as if it were merely an ornament to the dial. The 
seconds-hand, when properly placed, should be firmly secured 
upon its pivot, so that it cannot be accidentally shifted. If it 
is loosened up for setting, it must be afterwards pressed down 
again, which will frequently cause an error of one or two sec- 
onds, and perhaps the watch is stopped, or the upper fourth- 
wheel jewel cracked. Or, it may go on too far, and must be 
pried off again, making another error, etc. The quickest and 
best way is to stop the watch when the seconds-hand is just on 
the 60, by placing the bristle on the balance, which should be 
drawn around far enough to start instantly with a good motion 
when the bristle is raised. Then set your minute- and hour- 
hands. 

All trials and observations should begin and end when the 
seconds-hand on your regulator is at the 60, unless the sec- 



THE WATCH ADJUSTER'S MANUAL. 139 

onds-dial of your watch is imperfectly spaced off; if so, then 
at the nearest 60 upon that. 

(321.) Variations in running, — In regulating a watch, the 
workman should remember the distinction between an error in 
the rate and one arising from its not being in good condition. 
Having set it accurately, we examine it at intervals and com- 
pare its time with the standard. If it gains or loses an equal 
amount in each six hours after being wound and set, and four 
times as much at the end of the twenty-four hours as at the end 
of the first six, or even if it gains or loses the same amount in 
the last twelve hours as in the first twelve, the error is one of 
rate, and can be corrected by the regulator. In such case, we 
say it "gains," or it "loses," so much per day. But if it gains 
in the first twelve hours and loses in the last twelve, or the re- 
verse, then we say it "varies," and the fault is not in the rate 
but in the condition of the mechanism — generally a non-iso- 
chronal hair spring, (280, 517), and a variation in the motive 
force. The only remedy for this is to remove its cause, as 
directed in the Chapters on Isochronism. 

(322.) Regulating a varying watch. — Such a watch can only be 
regulated to produce a correct average at the end of each day, 
(280) and the customer must be impressed with the importance 
of winding it at precisely the same hour every day. It does 
not matter much what hour that may be, only he should choose 
one in accordance with his habits and which he will be sure to 
remember. Furthermore, he must compare its time with the 
standard regulator at the same hour of the day, for if he com- 
pares it in the forenoon at one time, and in the afternoon or 
evening the next time, regulating and setting on each occasion, 
his watch will soon keep no time at all. He may even set it in 
the forenoon, and in the afternoon of the same day find it a 
minute or two out of the way, while it may be right again the 
next forenoon, twenty-four hours after setting, if it is not dis- 
turbed. A workman who fully appreciates this point may make 
quite inferior watches give tolerable satisfaction, while if he 
alters the regulator for the customer whenever he happens to 
come in the shop, or allows him to do it himself, his reputation 
as a workman will soon "peter out." 

(.'h'^Z-^ Proper care of watches. — When watches are hung up 
they should not rest against a hard backing, as a plastered 
wall, etc., nor be allowed to swing upon their hooks. Nor 
should they be subjected to any jarring or trembling of the 
supports to which they are attached. Especially to be avoided 
is a regular or periodical jarring or thumping, whose intervals 



I40 THE WATCH ADJUSTER' S MANUAL. 

may be in unison with the vibrations of the balance, whether 
exactly so, or coinciding alternately, or in any similar way. 
They should also be protected from both cold and heat, mois- 
ture and dust, and the customers must be instructed not to lay 
them on marble, metal or other substance that will rapidly ab- 
stract their warmth. Watches should not be opened where the 
air is much warmer than they are, as the moisture of the air is 
condensed by contact with the cold movement, causing rust of 
the steel parts on which it settles. The workman must keep 
the watch as nearly as possible at a uniform temperature while 
regulating it. If it is to be compensated for heat and cold, that 
is a separate adjustment, which has nothing to do with the rating. 

(324.) Position at night. — If watches are hung up during the 
day, while regulating, they should retain the same position at 
night; and if laid down days, they should also be laid down 
nights. A common watch will vary in different positions, but 
you are not to attempt to correct that error by regulating. 
After it has been closely regulated for hanging, in the shop, the 
finishing touches should be given while it is in actual use, and 
subjected to the regular treatment customary with its owner, 
who should be i)ist7'ucted to follow precisely the sajne routine every 
day. If he carries it during the day, and hangs it up at night, 
he should hang it up evety night. If he lays it down at night, 
it should invariably be laid down, horizontally, and with the 
same side up, and protected as directed in the preceding section. 
Fine watches vary less from such causes, but they are also ex- 
pected to run more closely than others, so that these rules are 
beneficial in all cases. It is by attending to such little matters 
that satisfaction is given, and it cannot be done without. 

(325.) Ho7V to carry a watch. — If the watch cases are thin, 
they should be carried where no undue pressure can come upon 
them, to force them down upon the end of the center post, and 
stop the hands or the watch itself. Always examine the inside 
of the case to see if there are any marks of touching. If so, 
the post must be shortened or otherwise protected. Ladies' 
watches often run very irregularly, or stop, from being squeezed 
too tightly in their belts. But it is not much better to carry 
them in their bosoms, as they are kept too warm and moist. 
The best place is a pocket in the dress-skirt just below the belt, 
made of a size to fit the watch. The pocket should not be too 
low. As for chatelaine watches, the workman should never 
promise that they will keep good time, for it is impossible for 
them to do so — swung and flopped and jerked and knocked 
about in the way they are. The best place, for a man, is a 



THE WATCH ADJUSTER'S MANUAL. 141 

pocket in the pants, where the watch will rest upon the abdo- 
men, and be less affected by pressure and blows, than if resting 
against the unyielding ribs. 

(326.) Haw to correct errors. — If we find that the error in the 
rate of our watch is so great that the regulator will not correct 
it, or if the regulator is already at the limit of its sweep, our 
course must be guided altogether by the circumstances of the 
case. Certain remedies may be justifiable in cheap watches, 
which would not only be utterly inexcusable in fine work, but 
would render the workman liable to prosecution for malpractice 
and payment of -damages for the injury done. We will first 
consider the treatjnent of common watches, reserving the ques- 
tions connected with the regulation of the finest movements, 
without injuring any of their adjustments, for subsequent treat- 
ment, as there is considerable to be said on that subject. 

(327.) Altering the hair spring. — If the watch loses time, we 
can take up the hair spring enough to approximately correct the 
error, and finish by the regulator. Before taking off the balance- 
bridge, see if the watch is in beat. If not, notice in which 
direction the error is, and how much. An over-sprung watch, 
and some others, can often be put in beat without taking out 
the balance or stud, (removing only the balance-bridge,) by the 
use of the tool named in (51). But it is safer, generally, to 
take the balance out. First note the distance of the stud from 
the nearest arm of the balance, or from some screw in the rim, 
or other mark, and also the distance required to place it in beat, 
which will show what position the stud should have when in 
beat. Now draw the spring through the stud the proper dis- 
tance, and pin again. Next loosen the stud and take out the 
balance, bend the spring, if necessary, to bring it into proper 
shape (284, 285,) and move the collet around till the stud takes 
the correct position as noted above. See also (287). If the 
watch gains, we let out the spring in the same way. -^^ 

(328.) Grinding the hair spring. — But if it gains and we have 
no spare spring to let out, we have three remedies, besides fitting 
a new spring. First, we can grind the spring on its under edge, 
till we reduce its breadth and weaken it sufficiently. To do 
this, take a flat piece of soft cork, considerably larger than the 
spring and half an inch thick. Make one side very flat and 
smooth, then cut a hole in the center to allow the collet to be 
forced in with one or two central coils while the grinding is 
going on. In a watch of any value, the collet should be taken 
off the spring. Spread the spring evenly on the cork, which 
should first be oiled a little to secure its adhesion, then lay the 



142 THE WATCH ADJUSTER'S MANUAL. 

cork carefully down on a clean, sharp oil stone, or a ground 
glass plate smeared with oil stone dust and oil. Before moving 
the cork at all, press it down hard, to slightly imbed the coils 
in its surface, and cause them to retain their position while 
grinding, then rub it over the stone in circles in all directions, 
so as to grind the spring as evenly as possible. Keep the stone 
well oiled, (or the glass well supplied with oil-stone dust,) don't 
grind too fast, press the cork down flatly by the finger on its 
center, do not move the cork without pressing it down nor lift 
it up till you have finished. Then take it from the cork, absorb 
the oil by paper, and finish by soaking in alcohol, dry, replace 
the collet on the balance-axis, pin in the stud, put in beat and 
try. 

(329.) A better way. — A more perfect way, when the spring 
needs much grinding, is to remove the collet and cement the 
spring with shellac on the plate used by workmen for flat polish- 
ing, make the cement perfectly liquid by heat, press the spring 
down to the metal to get it flat, and hold so till cold. Adjust 
the leveling screws so that the spring will bear evenly on the 
polishing surface, then grind as much as thought necessary ; 
heat the polisher enough to remove the spring, and remove the 
shellac in boiling alcohol. Should the spring be soft, or from 
any other reason there should unfortunately be a " feather- 
edge" of metal on the coils, it must be removed by dipping the 
spring in acid, (330.) I have sometimes found springs on which 
the workmen had left long fibres like hairs, caused by this 
feather-edge splitting off, and preventing any proper motion of 
the spring. 

{.TiZ*^-^ Weakening with acid, — To weaken a spring with acid, 
it should first be cleaned from grease, etc., so that the action 
of the acid will be all over alike. This may be done by soak- 
ing it in absolute alcohol, or in a warm solution of caustic soda 
in water — such as is used to clean articles for electroplating. 
If the latter method is adopted, it should afterward be soaked in 
clean water, then in alcohol. It is best to remove the spring 
from the collet during this process, but if it is not, after drying 
it off, put a very little oil at each end of the hole in the collet, 
to fill the hole, and keep the acid out, or fill it with thick shellac 
and alcohol. The acid is made by mixing in a watch-glass five 
drops of water and one drop of the strongest sulphuric or nitric 
acid, or more in the same proportion. Or use chemically pure 
muriatic acid i part, and water 2 parts. This is best, as it 
does not blacken the spring like the others. Mix well with a 
bit of glass, and immerse the spring for a few seconds, or until 



THE WATCH ADJUSTER'S MANUAL. 143 

it becomes black. No time can be specified, as it depends on 
the strength of the acid, size of spring, and amount of action 
wanted, but great care must be taken not to eat the spring too 
much. 

(331.) Rinse the spring thoroughly in water, and soak it in 
the soda to completely neutralize the acid, then in alcohol, and 
finally dry it off between folds of tissue paper. If you have no 
caustic soda solution, a moderately strong solution of cyanide 
of potassium in water will do to neutralize the acid. If the 
effect is found to be not sufficient, the operation can be repeated. 
This process, if carefully performed, is safer than grinding, and 
more equal in its effects, but it blackens the spring, while grind- 
ing does not produce any change of appearance that is visible 
while running. To clean the spring from the black, put it in 
the muriatic acid solution above mentioned, which will leave 
the spring white, after which it can be blued, and its appearance 
be made as good as when new. See section (60). Or if the 
muriatic acid is used for weakening the spring and the cyanide 
for neutralizing it, the spring will not be blackened, but left 
white. And probably the acid process will least injure the 
isochronism of the spring, — a result which must in some degree 
follow every effort to alter the strength of a hair-spring, no 
matter how it is done. For this reason the following process 
may be preferable, as the hair-spring is not disturbed at all. 
But whenever any change is made, it should be as nearly equal 
as possible throughout the whole length of the spring. 

(332.) Making a plai?i balance heavier. — The third method is to 
make a plain steel, gold, or brass balance heavier, by tinning it. 
The spring and all parts that would be injured by heat must be 
removed, the lower surface of the rim scraped to get a perfectly 
clean surface, but the edges must not be scraped, lest the tin 
should run up on them. Then rub over the scraped surface a 
little soft-soldering-fluid. Now take a strip of thick sheet tin, 
i\ inches broad and 3 inches long, bent into the form of a let- 
ter Z, only the middle part is nearly vertical. The heat 
of the lamp is to be applied to the upper part, the middle being 
between the flame and the balance, and conducting the heat to 
the lower part, upon which some block tin is melted and spread 
all over its upper surface. Take the balance in the pliers, at 
the junction of an arm with the rim, and, when the tin flows 
freely, rub it on this lower portion of the Z till one-third of the 
rim is well tinned, then treat the other sections in the same way. 
No more heat must be used than is necessary to make the tin 
flow easily, as too much would color the balance. Wash off in 



144 THE WATCH ADJUSTER' S MANUAL. 

clean, soft water, without soap, then soak in alcohol and dry, 
being sure to remove every trace of the soldering fluid, which 
would rust the balance and other parts of the watch if it 
remained. To neutralize it, the balance, after washing, could 
be dipped into the soda-bath, (330,) or in water in which a little 
common carbonate of soda is dissolved. Then wash again, etc., 
as above. 

{2,c>Z') Take off any lumps with the scraper, level the surface 
of the tin, and poise properly without the spring, etc. Then fit 
on the spring, and proceed as in section (328). Many workmen 
do not allow that this operation is workmanlike, but if properly 
performed, and the change makes the weight of the balance 
more suitable than before, it would be difficult to raise any valid 
objection to it. Most certainly no injury, but an improvement 
has resulted: It must be distinctly understood that I do not 
justify the two first methods in any but cheap watches, and even 
then it is hard to see why the workman might not about as well 
fit a new spring, which he could afford to do for a very little 
more, and no one could find fault. If he has no suitable new 
spring, the foregoing methods may be excusable. But the 
practice of scraping springs is not excusable under any circum- 
stances whatever. It is botch-work and butchery, out-and-out, 
while the methods just named, if carefully carried out, may give 
very fair results, and the last one, results that are entirely 
unobjectionable. 

(334.) When not to regulate. — When the watch is running 
closely, do not regulate it too often. If it gains ^ minute in a 
day, leave it so and see if it has gained one minute, the next 
day. If so, it will then be safe to turn the regulator. If not, 
the watch may have been exposed to the sun, or to unusual cold 
or heat, or kept in a different position, or had different usage. 
In the same way, when the watch is running closely in the cus- 
tomer's pocket, do not alter it for a slight error, but tell him to 
remember how it is and try it a little longer. Common watches 
will vary more or less from the sort of usage they receive, and 
it is better not to correct each small error, but get them so they 
will average closely, whatever the variation may be from day to 
day, i.e., they may now be a little fast, and then a little slow, 
but the mean rate will be about correct. Another cause of 
apparent error in the rate, which in a cheap watch may amount 
to as much as one or two minutes, is a want of truth in the 
marking of the dial. The only remedy for this is to always 
compare the time when the minute-hand is at the same part of 
the dial, say at the figure XII. If the dial is not fastened on 



THE WATCH ADJUSTER'S MANUAL, 145 

concentrically with the main plate, i.e.^ the cannon pinion is 
not in the center of the circle of the dial figures and spaces, 
there will be an apparent error of rate, even when the watch 
runs correctly and the dial is perfectly spaced off. For instance, 
if the figure XII is too near the center post, the watch would 
be correct at XII and VI, but will appear to be fast at IX and 
slow at III. The error may be as much as a minute, and will 
diminish gradually in amount in each direction from those 
points, till the minute-hand reaches XII or VI, when it will dis- 
appear, to reappear as the hand goes beyond those points. 
This defect may be detected by training the point of the hand 
to run close to the dial, and turning it through one revolution ; 
the points which are nearest and furtherest from the center post, 
are the places where the watch should be compared and regu- 
lated. All watches with any such defects should be put in a 
corner of the board by themselves, to insure their receiving the 
special treatment they require. Also see sections (369, 373). 

(335-) Effect of ru7ining dmvn. — In conclusion, I may mention 
a fact not generally known: that if a watch which has been 
closely regulated is allowed to run down, its rate will almost 
invariably be different when again wound and set going — 
generally, it will gain. Whether the change of rate is due to 
the relaxation of the mainspring when relieved from tension, or 
whatever the philosophy of it may be, we may derive from the 
fact a useful practical lesson, — not only to guard against such a 
mishap while regulating our watches, but, when it does occur, 
to avoid moving the regulator to correct the error. Many 
watchmakers allow their watches to run down every Sunday, to 
save the trouble of winding on that day. This is a great mis- 
take, for it generally takes them several days to fully recover 
their former or permanent rate, and if the regulator is changed 
before this takes place, it is evident that an injury is done which 
will have to be undone again when it has returned to its normal 
condition. It is well to keep customers' watches running till 
they are called for, unless they are left for an unreasonable 
length of time. So, also, sale watches which have been closely 
regulated, and from which purchasers will expect fine perform- 
ance, should be kept running. But if they have been allowed to 
lie still for a while, no account must be made of their rate for the 
first week after rewinding — simply giving that time for them to 
settle down again. At the end of the week, set them, without 
changing the regulator, and they will generally run the same as 
before. If they do not, it will then be safe to move the regu- 
lator, and bring them to time in the usual way. 
10 



146 THE WATCH ADJUSTER'S MANUAL, 

CHAPTER XXII. 
Regulating Fine Watches. 

(^2iZ^-^ Regulating fine watches. — We will now consider the 
regulation of fine watches, in which it is not expected, of course, 
that any great change will be necessary, as in that case a new 
spring would be fitted. Supposing that we have an isochronized 
hair sprifig^ it must not be let out nor taken up to change the 
rate, but we must alter the balance. Even if the watch has a 
regulator, it should be moved but very little, as by so doing we 
virtually change the length of the spring, and injure or destroy 
the isochronism. After moving a regulator to change the rate 
to the extent of half a minute per day, or more, the isochronism 
should be tested, and if it has been injured by the change, the 
regulator should be replaced where it was, or where the isochro- 
nism will be restored, and the rate be corrected by the balance. 
This is important in all cases, but particularly so in springs with 
terminal curves. Of course, in watches without regulators, the 
rate is to be corrected by the balance only, according to the 
directions given in the chapters on Rating. But as most 
watches have them, the greater portion of this chapter is devoted 
to them. 

(337. ) The proper fitting of the seconds-hand \s din important point 
in timing fine watches. It should fit the pivot closely enough to 
avoid any risk of accidentally changing its position by being 
touched, but not be really tight, as the pivot is liable to be bent 
or the jewel cracked by getting it off, and the cock loosened or 
sprung or jewel injured by pushing it on. The dial hole must 
be large enough to render it impossible to touch the socket of 
the hand or for a little dirt or fuzz to clog between them. The 
upper end of the dial hole should be a little countersunk for 
safety. The rule is to be sure fiothing can affect the seco7ids-handj 
give too much clearance, rather than not enough. In the 
duplex, center-seconds watches, etc., be very particular that the 
outer surface of the seconds-hand socket shall be perfectly free. 
When the pipe is long, it is customary to broach it out to fit 
loosely on the pivot, then squeeze it in at the middle, to fit 
snugly. That is wrong, for the pipe is generally split thereby, 
and even if it is not, it will seldom stand truly on the pivot, but 
one side will stick out, and is almost sure to rub somewhere; 
the index part is also out of level. The proper way to fit a long 
pipe is to broach it equally from each end, so that it will fit the 



THE WATCH ADJUSTER'S MANUAL. 147 

pivot from the lower end to the middle. Then if the pivot is 
vertical the hand will clear the dial equally all around. If you 
are fitting the hand on a chronometer or duplex which is to- 
gether, put a slip of paper under the balance (when at the point 
of rest) to hold it still while you are doing the job. But the 
proper time to fit a seconds-hand is while the fourth wheel is out 
of the movement, or, at least, the escape wheel is out. Let no 
oil get on the pipe or socket, or in the dial hole, while the watch 
is together. 

(338.) Positions of the hands. — The dial must first be fastened 
so that it not only cannot move about and change its position, 
but will not work loose in a little while, even when the watch is 
roughly used. Be sure about that. The dial should of course 
be concentric with the plate, and so that the hands will all come 
in the centers of the dial openings, and be free (20 to 22). But 
if the dial openings are not central with the graduated circles, 
the hands must be at the centers of the circles. In doubtful 
cases, watch the point of the seconds-hand once around. 

(339.) The dial. — Fig. 9, section (165), will show the necessity 
of correctness in a fine watch. The fourth wheel pivot is shown 
out of center — at the left side of the opening. The two lines 
passing through the figures show the divisions of the dial. If- 
the seconds-hand points to 60 at the beginning of the minute, 
it will point to a in 30 seconds, (half a revolution of the wheel,) 
showing more than 30 seconds on the dial; and at the quarters 
it will point to b and ^, instead of 75 and 4^. Fig. 8, section 
(165,) shows the pivot in the vertical center of the circle, but 
above the horizontal center. The hand would be correct at 60 
and 30 seconds, but nowhere else. At the quarters, it would 
point to e and d, instead of 75 and 4^. 

(340.) Testing the dial. — A good way to test the position of 
the pivot, is to lay a straight edge of brass, or even paper, across 
the dial between 60 and 30. If the center of the pivot is exactly 
on this line, it is in the vertical center. Then lay it across 
between 75 and ^j, to see if the pivot is in the horizontal center. 
If not correct either way, it should be made so. When right, 
if there is any doubt about the equality of the marking, cut out 
a small paper circle to fit inside of the dial circle, prick a fine 
hole at the center, slip it on the pivot, and mark on its edge the 
exact positions of the 60, 5, 10 and 15 of the dial. With this 
gauge test the other quarters of the circle. The equality of the 
seconds marks can be told closely enough by inspection. An 
imperfect dial makes rating or fine timing much more difficult,, 
as will presently be seen. 



148 THE WATCH ADJUSTER'S MANUAL. 

(341.) To set a chronometer to ti??ie. — The only perfectly safe 
way is to stop the watch, and start it again when its seconds- 
hand agrees with that of the regulator. It is not safe to force 
the seconds-hand ahead, nor back, nor even to hold it still 
(510). Stop the balance at the point of rest, so that it will 
remain still till you start it. Stop it with the seconds-hand 
exactly on the 60; that is the best way, although either of the 
quarters will do, if the dials are perfectly divided off. To get 
the hand exact, stop it a second or two too soon, then with the 
bristle move the balance each way far enough to escape and 
lock, and look at the hand. If necessary, repeat it — each time 
bringing the balance to the point of rest before freeing it. 
When the seconds-hand stands exactly at the 60, you start the 
watch at the instant the regulator hand strikes its 60. 

(342.) To sta?'t the chronometer on time. — You can do this either 
with the bristle, or by shaking. If you choose the latter, you 
hold the watch so that you can give it a circular twist by a 
motion of the wrist, and keeping your eye on the regulator, at 
the instant its hand comes to 60 twist the watch and start it. 
A little practice is necessary, to start them exactly together. 
The watch must be twisted in such a way that the balance 
makes its impulse vibration.^ (4^5 >) i^ot the dumb vibration — and 
it begins to move immediately. Remember that the bala?ice 
stands still while you twist the watch, and thus move the escape 
wheel around the roller, instead of the balance and roller re- 
volving. Only the one twist is necessary — more than that would 
be liable to cause tripping or over-running. By the other way, 
with the bristle, you simply move the balance one-quarter turn 
from the point of rest, (the dumb vibration,) and hold it still till 
the regulator hand touches the 60, then lift your bristle and let 
the balance make its first impulse vibration. Some practice the 
following method. 

(343.) To set a chronometer forward or back. — Stop it the 
proper length of time, then start it again. If it is 10 seconds 
fast, stop it with its seconds-hand on its 60; and 10 seconds 
later, when the regulator reaches 60, you start it again, either 
by shaking or twisting, as before described. If it is only a few 
seconds fast, say 3 seconds, you can get the motion of the bal- 
ance in your mind closely enough to count the proper number 
of vibrations while you are holding the balance still, then let it 
go. With an ordinary 18,000 movement, 3 seconds would take 
15 vibrations, — or a little over 7 pairs, if you count only each 
alternate vibration. Holding the watch in convenient position, 
you begin counting by saying " one" as you lower the bristle 



THE WATCH ADJUSTER' S MANUAL. 149 

upon the balance, which you hold till you reach 15 (or 7), then 
lift the bristle and look. It is always safer to start it a little 
too soon, than to hold it too long, for it is easy to stop the 
motion for an instant (one or two vibrations) and so get the 
hand exact. The only safe way to set the hands forward, is to 
stop the watch and get the seconds-hand correct, as above, then 
set the minute-hand forward one minute — or more, if required. 
Many workmen practice the following method with the chro- 
nometer, but it is not safe. 

(344.) To set a duplex to time. — It is not safe to twist the sec- 
onds-hand around on the pivot, but there is little risk in holding 
it still by means of a key on the center or setting post, till the 
regulator seconds-hand comes to the same point — preferably the 
60. But if the watch hand is slow, it should be held still and 
made slower yet till it agrees with the regulator, then set the 
minute-hand correctly, as described for the chronometer (343). 
A better way is to follow precisely the method there given, for 
setting the hands either forward or back. When the duplex is 
only a few seconds slow, many workmen give it a twist and 
make it " overrun" (498) a few vibrations to catch up, but that 
is a rather rough way of doing it. Besides, it may overrun too 
long, and get too far ahead, unless you stop the balance fre- 
quently and compare. 

(345.) Setting the cylinder or lever to time. — It does no harm to 
set these watches backward, if in good condition. But it is 
seldom advisable to disturb the seconds-hand after it has been 
perfectly adjusted on the pivot. It is better to get the hand 
back (if too fast) by holding the escapement still with a key on 
the center post, till it agrees with the regulator. Or else press 
the center (or fourth) wheel backwards with the screwdriver 
till the seconds-hand has been sufficiently delayed. But the 
best way is to hold the watch so you can see the dial in a mirror 
underneath, stop the balance with the seconds-hand just on its 
60, hold it there (drawn partly around) till the regulator hand 
comes to 60, then lift the bristle and let the balance go, and 
set the minute-hand. If only a second or two too fast, touch 
the balance with the bristle long enough to stop it for two 
or three vibrations and compare, then repeat as needed. If the 
seconds-hand is behind time, stop the balance till the seconds 
hand agrees with the regulator, then liberate it, and set the 
minute-hand ahead. Some stop the seconds-hand by putting 
the end of the bench key before the point, hold it till it gets 
with the regulator, then start as before. 

(346.) Regulating by the timing screws. — In genuine chronome- 



150 THE WATCH ADJUSTER'S MANUAL. 

ter or compensation balances adjusted for temperatures, there 
are generally four mean-time screws, — two at the ends of the 
center-bar, and two others midway between them on the rim, 
being thus a quarter of a circle apart, and hence also termed 
" quarter-screws. " The office of these timing screws is to adjust 
the rate of the watch, by screwing them further in, and thus by 
carrying their weight nearer to the center of the balance, to 
make it virtually smaller or lighter, and cause the watch to 
gain; or turning them out further from the center, to make the 
balance virtually heavier, and lose. Any alterations should of 
course be made equally on the two opposite screws, to preserve 
the poise of the balance. This can be done by noticing the 
slits in their heads and giving each one exactly the same angle 
of turn. If there is any doubt, the poise should be tested. 
Should it be found incorrect, the two screws must be made to 
restore it. But inasmuch as all watch manufacturers do not use 
four mean-time screws as above, it will be safer to alter only 
the tuw at the end of the center-bar. In any case, the other 
pair must never be changed more than a mere trifle, because 
any change of a screw upon the cut section of the rim, by mov- 
ing it either in or out, must infallibly disturb the compensation 
for heat and cold. Even if a cut balance is not adjusted, it is 
not advisable to alter the screws near the ends of the sections, 
but only those near the center-bar, where their effects upon the 
compensation, or the errors caused in different temperatures, 
will be less in amount, although the effect upon the regulation 
will be just as great. 

(347.) Chronometer balance. — Not all cut balances, even when 
they are genuine chronometer balances, are compensated; and 
whether any particular balance is adjusted or not can only be 
certainly known by trying it in different temperatures. There 
are very few makers whose stamp, "adjusted," may be fully 
trusted without trial. A cut balance that is not adjusted may 
be either better or worse than an uncut balance; as it may hap- 
pen to be very near correct, or, on the other hand, the position 
of the screws and the action of the sections of the rim may be 
so unsuitable to each other as to cause the balance to " act like 
the devil," when exposed to changes of temperature. As the 
adjustment of the compensation balance for heat and cold is a 
special subject by itself, I shall not consider it here, but merely 
observe that it is important to keep our watches at a tempera- 
ture as nearly uniform as possible while regulating them, in 
order to eliminate from our task all the irregularities which 
would otherwise be mixed up with the action of the hair spring. 



THE WATCH ADJUSTER'S MANUAL. 151 

We can regulate a watch in one temperature, but we cannot, if 
we try, make tiie regulation cover the compensation for temper- 
atures, and by trying we shall not only fail in that, but injure 
our regulation besides. This rule is especially important with 
cheap watches. And the best are always regulated in one tem- 
perature and compensated in differeiit temperatures. 

(348.) Screw balance. — If we have an isochronal spring with 
a screw-balance which is not cut, we can alter any or all of the 
screws in the rim indifferently, so long as we do not destroy the 
poise. If the watch loses, we must make the balance either 
actually or virtually lighter. If the screws cannot be turned 
in, we may either file off the heads a little, taking care to do 
this squarely and in a workmanlike manner, or we can drill out 
in the center of the heads, leaving the exterior appearance un- 
changed. Some workmen file out the slots wider and deeper, 
in the heads, when only a slight alteration is needed. Or we 
can take out gold screws and substitute lighter ones of brass, or 
smaller gold screws. Or, if change enough is required, we can 
remove an opposite pair of screws entirely. On the other hand, 
if the watch loses, we can turn out one or two opposite pairs a 
little. If that is not sufficient, turn others equally far out, 
being careful not to draw out either of them more than the rest, 
and drawing out more screws rather than move a few too much. 
We can also put gold washers under the screw heads, or substi- 
tute gold or platinum screws for those of lighter metal, or sub- 
stitute larger screws, or put in an additional pair to increase the 
weight of the balance. These changes of weight, if consider- 
able, will slightly disturb the isochronism of the spring, which 
must be readjusted as hereafter directed. If the watch has a regu- 
lator, the isochronism can generally be restored by opening or 
closing the pins, (585,) or, in the case of a terminal curve, by 
slightly altering that, after the watch is closely regulated for 
time. But the isochronism should never be corrected by the 
regulator pins with any but the plain flat spiral springs, and not 
then, if a better method can be followed. 

(349.) Making a plain balance lighter. — If, instead of a screw 
balance, we have a plain one, whether of gold, brass, or steel, 
the best way to make it lighter is to hold it by the exterior of 
its rim in one of the step chucks of the American lathe, or any 
similar way, and turn out a very little with the graver, on the 
under side, being careful not to cut away too much. In this 
way, with due caution, the poise will not be disturbed. Others 
simply file a little from the inner edge of the under side of the 
rim, equally in three different places, to preserve the poise. 



152 THE WATCH ADJUSTER'S MANUAL. 

The only way to make a plain balance heavier is to tin it, 

(332). 

(350.) The effect produced upon the isochronism of a hair spring 
by 7noving its regulator is, in general, greater in the short vibra- 
tions than in the long ones. Turning the regulator towards the 
"slow" makes all the vibrations slower, but the short ones pro- 
portionately more so than the long ones. And, vice versa^ turn- 
ing the regulator towards the " fast," not only makes the watch 
gain, but also causes the short arcs to gain on the long ones. 
If the spring is isochronal, and the watch gains or loses but lit- 
tle, the error of rate should be corrected, not by the regulator, 
but by altering the balance. But if the balance has no screws, 
such alteration would be troublesome, and we may prefer to 
move the regulator to correct the rate, and then restore the 
isochronism by opening or closing the regulator pins a little. 
This course is more often allowable when the required motion 
of the regulator is towards the stud than when away from it. 
But when the error of rate is considerable, we must move the 
spring through the stud, bearing in mind the requirements of 
isochronism, in the flat spiral spring, (the Breguet spring will be 
specially noticed) as to maintaining the relative positions of the 
points of attachment, etc. That is to say, after taking up or 
letting it out, we must restore their previous relative position, (if 
correct,) by altering the central coil. If that alteration of 
the spring, etc., is not allowable or practicable on account of 
destroying the correct proportions of the central coil, (275, 276,) 
or for any other reason, then we must change the weight of the 
balance to the required amount as already described, or, if too 
much change is needed, a new spring should be fitted; for we 
must perform the regulation in such a way as not to destroy 
either the harmonious proportions of the movement or the 
isochronism of the spring, and to improve both if possible. 
Also, see Chapter XXIII. 

(351.) Duty of the workma?!. — But it is always a grave ques- 
tion for the workman to answer to his own sense of right, how 
far he is justified in permanently altering a watch by changing 
the weight of the balance, to save himself the trouble of fitting 
a new spring. Even in cheap watches he would require a strong 
excuse for removing or adding a pair of screws, or very much 
changing the weight of a balance by tinning or filing it; and in 
good watches it could only be allowed on the supposition that 
the weight of the balance did not bear a correct proportion to 
the motive force of the mainspring. If this proportion was 
correct, then his duty would be to conform the strength of the 



THE WATCH ADJUSTER' S MANUAL. 153 

hair spring to the weight of the balance, so that the balance and 
hair spring, as an entirety, would be suitable to the movement. 
The altering of the balance to conform to the strength of the 
hair spring, in such a case, would destroy the correct proportions 
of the entire movement, and such a practice should only be fol- 
lowed within very narrow limits. 

(352.) In watches with regulators^ the adjustment of the 
isochronism becomes more difficult as the distance of the pins 
from the stud increases. So much so, that many high authori- 
ties have claimed that a spring cannot be isochronized at all 
with a regulator, probably because, in bringing the watch to 
time, they had got the regulator too far from the stud. There 
is no denying that, theoretically, the action of the pins renders 
a perfect progression in the increase of elastic force impossible, 
— since the spring cannot vibrate as it would if it ended at the 
regulator, nor as if its action extended to the stud uninfluenced 
by the regulator, but there will be a mixture of the two, varied 
by the effect of the pins, and further complicated by the reverse 
action of the portion of the spring between the pins and the 
stud. But, practically, if the spring has been fitted in accordance 
with the instructions heretofore given, and the pins are near the 
stud, we can so add to or take from the composite action result- 
ing from all these different influences, as to secure a correct 
progression of strength, and consequently isochronal vibrations. 
The workman should endeavor, in regulating his watches with 
flat spiral springs, to keep the regulator as near the stud as 
possible, not only for the sake of the isochronal perfection of 
the spring's action, but because even the regulation to time is 
more easily and closely effected by so doing. It should also be 
remarked that the effect of opening or closing the pins increases 
as they are nearer to the stud, so that the isochronal adjustment 
is more easily made, or restored, when disturbed by moving the 
regulator. If the regulator cannot be got within 20° or 25° 
from the stud when the rate is correct, it is well to move it to 
different positions, and test the isochronism in each, to find the 
best place — paying no attention to the rate till the point is 
found where the isochronism is nearest correct, then bring to 
time by the balance screws. But if this will take the regulator 
more than 45° distant from the stud, it is better to take up the 
hair spring, to bring the regulator back, then adjust the 
isochronism. 

(353-) With cofnplete or fractional coils. — Many workmen claim 
that when the regulator is more than 20° or 25° from the stud, 
the even coils should invariably be reckoned from the point 



154 THE WATCH ADJUSTER' S MANUAL. 

touching the collet to the regulator pins instead of to the stud, 
(566.) And if the watch does not give correct time with the 
regulator in that position, the balance screw should be altered. 
It should also necessarily follow that if the hair spring has to be 
taken up or let out, the regulator should be moved correspond- 
ingly, in order to retain the whole coils; and when the isochro- 
nism is correct, if the rate is not, then the latter should be 
corrected by the balance, not by moving the regulator, as that 
would again destroy the isochronal adjustment. If these views 
were correct, then any change in the length of the spring which 
might be required to secure isochronal vibrations, could be made 
by simply moving the regulator in the proper direction and dis- 
tance, afterwards restoring the rate by the balance screws. But 
they are not correct, as a rule, although they are, to some ex- 
tent, in many cases; as, for instance, when the regulator is 
altogether too far from the stud, say from one-quarter to one- 
half coil distant. In such a case the isochronal action would 
probably be better if the even coils were taken from the collet 
to the regulator pins than if to the stud. But in neither case 
would the action be as good as if the parts v/ere all in the 
positions we have before recommended. It has elsewhere been 
stated that the theory of even coils is merely approximative in 
any case, (565,) and the actual position of the isochronal point 
in the spring must be found by trial. So that, even when their 
views are in the main correct, they must be followed with this 
qualification. 

(354.) Regulating a Breguet spring. — It has already been 
stated that, before taking down a watch with an isochronized 
hair spring, the workman should examine and make a minute 
of the position of the regulator, the position of the spring be- 
tween the pins, and the width of opening, in order to restore 
everything to precisely the same condition when done. This is 
especially important with a Breguet spring, for reasons before 
given. But when an error of rate requires the status to be 
changed, there are certain points to be observed in the regula- 
tion of the Breguet spring different from that of others. We 
first ascertain whether the terminal curve extends to the stud, 
or only to a concentric arc or portion of a coil, which is pinned 
to the stud, i.e.^ whether the concentric arc is a part of the ter- 
minal curve, or is separate from it. In the latter case, the over 
coil is a combination of a terminal curve with a concentric arc; 
in the former, it is all terminal curve. This can be told by mov- 
ing the regulator, if it is concentric with the balance. So far as 
the spring retains the same position between the regulator pins. 



THE WATCH ADJUSTER' S MANUAL. 155 

the coil may be considered concentric. But if the spring, from 
being free between the pins, soon presses against the outer pin, 
as the regulator is moved away from the stud, the point where 
this outward divergence begins may be considered the end of 
the terminal curve, from which point it sweeps gradually out- 
ward till it reaches the normal spiral form at the exterior coil of 
the spring. When the regulator is concentric with the concen- 
tric part of the spring, however, and not concentric with the 
balance, it shows that the terminal reaches to the stud and should 
be regulated as in the former case. This can generally be told 
by holding the balance cock up to the light and looking through 
the end stone — or removing the latter. If the center of the 
regulator is not over the jewel hole, it has been made concen- 
tric with the spring, instead of with the balance. 

(355.) With terjuijial curve to the end. — If the former is the 
case, or the terminal curve extends to the stud, the workman 
should conduct the regulation to time with the aim to get the 
regulator as near to the stud as possible. And to this end, he 
should make the watch go slower by moving the regulator 
towards the stud; but he should not move it from the stud in 
case the watch must be made to go faster, but, if practicable, 
produce that alteration by means of the balance, (769.) If he 
was able, without much change in the weight of the balance, or 
alteration of its screws, to cause the watch to gain sufficiently 
to allow of bringing the regulator entirely to the stud, it would 
certainly be wise to do so, for he would obtain the very best 
conditions for the perfect action of the terminal curve — simu- 
lating a spring without a regulator. The more closely to the 
stud he can bring it, the more nearly will the curve be free 
from restraint, and able to produce the legitimate effect sought 
for by its form. When springs whose curves reach to the stud 
are provided with regulators, every shifting of the regulator 
must be accompanied by a bending of its pins whenever neces- 
sary to make it conform properly to the spring in its new posi- 
tion ; but the spring must never be be7it to give it freedom between 
the pins and the regulator., as that would at once destroy the cor- 
rectness of the terminal curve. 

(356.) With concentric arc at the end. — On the other hand, 
if there is, between the end of the terminal curve and the 
stud, a concentric arc, (354,) distinct from the terminal curve, 
then his aim should be to bring the regulator to the point where 
the spring changes from a concentric to a divergent form. When 
the watch loses, he should move the regulator from the stud 
towards that point, and when it gains, he should not move the 



156 THE WATCH ADJUSTER'S MANUAL. 

regulator back, but draw out the screws of the balance. When 
the watch keeps time with the regulator at that point, and with 
the pins well closed together, the position of all the parts is the 
one most favorable for securing isochronism that the spring, in 
its then shape, is capable of giving. If the isochronal action is 
not satisfactory, the curve should be altered. When the concen- 
tric arc is a part of the curve, as explained in section (354), regu- 
late as for a curve reaching to the stud, (355.) 

(357.) With too lo7ig concentric arc. — But the preceding section 
is correct only when the concentric portion is within certain 
limits. If its lengih exceeds 45°, it is evident that the supple- 
mental coil has not been formed with proper regard to the 
requirements of isochronism, and we shall obtain better results 
by modifying the course taken in section (356). If the watch 
loses, the correction should not be made either by the regulator 
or by the balance, but by drawing the spring through the stud ; 
while, if it gains, the balance screws should be drawn out. If, 
by taking up the spring and drawing out the balance screws to 
a reasonable extent, we can bring the end of the terminal curve 
(and the regulator pins) within 45° from the stud, or less, we 
may hope for fine action of the spring. But if that point is 
more than that distance from the stud, even though we have 
the regulator pins at the end of the terminal curve, we cannot 
expect perfect isochronism. The regulator should never be 
moved beyond that point, and on the terminal curve, to make 
the watch go faster, but either take up the spring or turn in the 
balance screws to cause the gain in time. Nor should the spring 
ever be let out to produce a slower rate, if that alteration would 
carry the ends of the curve more than 45° from the stud, but 
we should draw out the balance screws for that purpose. 

(358.) Recapitulation. — Lest this subject should seem compli- 
cated, I will recapitulate briefly, ist. If the terminal curve of 
a Breguet spring reaches to the stud, the object should be to 
conduct the regulation or alterations so as to bring the regulator 
as near the stud as possible; and rather than move \X. from the 
stud, the balance should be altered. 2d. If there is a concen- 
tric arc at the end of the spring, distinct from the terminal 
curve, the aim is to bring the regulator to the junction of the 
concentric and divergent portions of the spring, and all altera- 
tions should be made to favor that purpose. But if the concen- 
tric arc \s a part of t/ie terminal curve, (shown by the regulator 
not being concentric with the balance,) the aim should be as 
stated under the ist head. 3d. But if its junction is over 45° 
distant from the stud, the chief obejct is to reduce that distance 



THE WATCH ADJUSTER'S MANUAL. 157 

to 45°, or less, and the next is to bring the regulator to the 
junction; and all changes must be made so as to favor the first 
object, if at all possible^ and if not, then to favor the second. 
Whenever any of these changes disturb the isochronal adjust- 
ment, it should of course be restored, in the most convenient 
way. 

(359.) These directions are based on the supposition that the 
workman is willing to take a little extra trouble for the sake of 
improving the isochronal action when it is not perfect. But if 
he cares for nothing but to bring the watch to time in the easiest 
way that will do no harm, or as little as possible, he should 
make his corrections of the rate principally by the balance. 
But whether he does or does not observe these rules, he will at 
least know how he may secure the most perfect results, if he so 
desires, or how to avoid injuring the timepieces in his care, when 
he has the choice of modes in which to make necessary altera- 
tions. If he only travels a little way in the paths recommended, 
or even only avoids taking wrong ones, that will be much better 
than working in the dark, not knowing whether he is improving 
or ruining his jobs. 

(360.) There are different degrees of excellence in Breguet 
springs, represented by the three preceding classes, in their order. 
Yet even the third and lowest degree, with a concentric arc 
greater than 45° and the regulator far from the junction, is 
without doubt much better than a plain flat spiral not isochronized 
at all, because the outer coil of the former can contract and ex- 
pand more evenly on all sides of the balance axis. But we 
should not be contented without doing in every case the very 
best we are capable of doing. If we are fitting a spring, let us 
fit it in the manner that will give the best action; if we are only 
regulating a spring already fitted, let us strive to obtain the best 
results which the form of the spring can yield. Only thus can 
we improve in our art, impress upon our memory the maxims 
which lead to perfection, familiarize ourselves practically with 
the finer manipulations, and gain the delicacy and dexterity 
which we should need if we were called upon to do a perfect 
job, but which we could not possess unless we had obtained 
experience by following the above course in our work, even upon 
cheap jobs or those in which we get no pay for our extra care. 



158 THE WATCH ADJUSTER'S MANUAL. 

CHAPTER XXIII. 

,^^ Rating. 

/ (361.) What is rating ? — The term timing includes all opera- 
tions for bringing the watch to time, while rating relates to the 
finer classes of timekeepers which, either naturally or by special 
adjustment, are more or less perfect isochronally, in positions 
and in different temperatures. Strictly speaking, rating is 
ascertaining the regular gain or loss of a watch in certain con- 
ditions, but in practice the term is also applied to the perfecting 
of the adjustment and the reduction of the errors to the small- 
est possible amounts. That being done, the error which remains 
\ is said to be the rate. 

^ (362.) The daily rate is the amount the watch gains or loses 
in a day, as compared with the correct time. If it gains 2 seconds 
in a day, we say the daily rate is -{- 2"; if it loses 2\ seconds, 
the rate is — 2.4". If it gains at times, and loses at other 
times, but never gets more than 3 seconds out of the way, the 
daily rate is ± 3", i.e.^ it may be either fast or slow 3". 

i^2>(i2)-) ^^^^ mean daily rate is obtained by adding together the 
gains and the losses in a certain time, and the excess of gains 
over losses, or the reverse, divided by the number of days, gives 
the mean daily rate. Thus, if it gained 7 seconds on 4 days 
and lost 22 seconds on 6 other days, the net error in 10 days 
would be a loss of 15 seconds, or a mean daily rate for the 10 
days of — 1.5". If that excess was a loss of i second, the 
mean daily rate would be only .1" — which may be a very decep- 
tive way of stating the error unless one takes care to notice 
whether the word " mean" is used. 

(364.) The operations which constitute the adjustments for 
isochronism, positions and temperatures will be treated under 
those headings. We shall here deal only with the means and 
methods of observing and comparing times, detecting errors, 
and deciding upon the proper remedy. The first requisite, of 
course, is a regulator (or other timekeeper) which keeps as 
nearly perfect time as possible. We of course do not recom.- 
mend any particular kind or maker, but merely suggest that the 
workman who aspires to do fine work should get as good a 
regulator as he can afford. We have already stated some of the 
requirements, and how it should be used to obtain good service 
from it, in Chapter XII; also the other conveniences for timing. 
Be sure to always have a pencil and pad handy on the bench. 



THE WATCH ADJUSTER' S MANUAL, 159 

(365.) Comparing the watch with the regulator. — The best 
method available to the ordinary watchmaker is by using the 
chronograph, as directed in Chapter XIII, as he then has a 
record of the difference of time between them exact to \ second, 
which he can examine at his leisure and ascertain the precise 
amount. That is closer than he can compare them by eye with 
any certainty, and it is evidently important to find the error as 
precisely as possible, especially in making the adjustments. In 
a 6 hours' trial the whole error may not exceed i or 2 seconds, 
and a difference of half a second in comparing times would be a 
large proportion of the whole error. 

(366.) Comparing by vibratiotis of balances. — Those who are 
quick of perception can compare with equal, or even greater 
closeness, by using a closely regulated watch and comparing the 
vibrations of the two balances, as directed in Chapter XV. By 
this method it is necessary, (unless you watch the trial balance 
closely enough to know that it has not gained or lost one or 
more whole vibrations, as well as the fractional part which you 
are comparing,) not only to set the two balances to vibrating 
synchronously, but to set the seconds-hands so that each will 
indicate the same number of beats on their dials. You first com- 
pare the seconds-hands, to see if they both strike a certain 
division mark exactly together, or if your watch is one or more 
beats (movements of the hand) before or after the timing 
watch. Each beat indicates an entire vibration (in the chro- 
nometer, it indicates 2 vibrations) gained or lost, besides the 
whole seconds, if any — in addition to the difference you may 
now discover in the phase of the balance vibrations. But as 
before stated, the principal value of this method of comparison 
is when the difference of phase is the only difference there is. In 
such cases, it is the closest of all methods of direct comparison. 

(367. ) Cof?iparing by seconds-hands has just been described, when 
two watches are compared. In comparing the trial watch with 
the regulator, you must of course set the watch so that its sec- 
onds-hand strikes a division mark at the same instant that the 
regulator hand does, and you can then find the error of your 
watch in seconds and beats, i.e.^ in an 18,000 movement, in sec- 
onds and fifths of a second. If the seconds dial is evenly divided 
and the hand central, (334, 338,) this comparison of beats can 
be made anywhere on the circle. If not, it should be made near 
the 60. The same rule governs in the comparison of seconds, 
and minutes. The method differs a little when the watch is slow 
or fast, as follows. 

(368. ) Co7?iparing times when the watch hand is slow., i.e. , in case 



i6o THE WATCH ADJUSTER'S MANUAL. 

the seconds-hand of the watch is between 30 and 60 when the 
regulator hand strikes its 60. This is the usual way, and is de- 
scribed in Chapter XV, especially in section (198), and also 
under the head of timing bells (209). Getting the swing of the 
seconds pendulum, or the jump of the clock hand, well in mind 
so that you can nod your head in unison with it without looking 
at it, you begin to count the seconds backward at 55 seconds, 
following up the watch hand with your finger-nail on the 
glass, saying " Five — Four — Three — Two — One — Naught" — the 
" Naught" being at the instant the regulator hand strikes its 60, 
and at the same instant you begin to count the beats on your 
watch till its hand reaches the next seconds mark after the 
*' Naught." Hold your nail there, till you have ascertained how 
many seconds the mark is before the 60. If it is 11, and you 
counted two beats after the " Naught" before the seconds-hand 
reached that mark, your watch is iif seconds slow. 

(369. ) The same with imperfect dial. — If the watch seconds-dial 
is poorly spaced off, you should only compare when its hand 
reaches its 60, by observing how many seconds that occurs after 
60 on the regulator dial. Get the period of the jumps or 
motions of the watch seconds-hand well in mind, so that you 
can nod your head in unison with them while you close your 
eyes a moment, or lift them to look at the clock, and can find 
the nods still in unison with the jumps when you look at the 
hand again. As your seconds-hand gets up near the 60, you 
can count the number of beats it gives after the clock hand 
strikes a seconds division and before the watch hand strikes its 
next seconds mark. That gives you tht fraction of a seco?idth.2it 
your watch is slow. You then keep the edge of your finger-nail 
just in advance of the mark the clock hand is at, drawing it 
back at each second to correspond, /.<?., you mark on the watch 
dial with your nail, at each second, the position the hand occu- 
pies on the clock. This is in order that you can have a sort of 
record of the position of the hand, so you may count up the 
number of seconds with certaint)'', at the end of the trial. You 
can do that on the minute circle of your watch, when the marks 
are plain and wide apart. 

(370.) Ascertaining the difference. — As your watch hand gets 
to 55 seconds, place your nail on the mark (on the watch), when 
the clock hand is at that second. (Some workmen put the nail 
5 seconds ahead of that, />. , where the clock hand will be, when 
the watch hand strikes its 60, and hold it there.) As the watch 
hand strikes each successive seconds mark, draw the nail back 
I second to correspond, and at the instant the watch hand 



THE WATCH ADJUSTER'S MANUAL. i6i 

strikes 60 you say "one, two," etc., looking at the clock and 
counting the beats till the clock hand reaches the next seconds 
mark. Then hold your nail there and count the seconds from 
the previous mark back to the 60. If that was 17 seconds, and 
you had counted 3 beats, your seconds hand is lyf seconds 
ahead of the clock hand. 

(371.) Cotnparing tifnes when the watch hand is fast ^ i.e. , in case 
its seconds-hand is after the 60 when the clock hand is at its 60. 
The usual way is similar to that described in section {^z^^'> ex- 
cept that in this case you place the nail just before the watch 
seconds-hand, and draw it back as the hand approaches, till the 
clock hand strikes its 60, then hold it still, and the number of 
seconds between the 60 and that mark on the watch dial shows 
how many seconds the watch hand is ahead of the other. You 
count the beats from each seconds mark (on the watch) to the 
next, then repeat. In an 18,000 movement, you would say: 
"one, two, three, four, five," and repeat it each second, looking 
at the clock hand to see which number you pronounce as the 
clock hand strikes its seconds marks. If it does so just as you 
say "three," each time, that shows that your watch seconds are 
three beats earlier than the clock seconds. 

(372.) To find the number of seconds. — Then find the seconds 
by counting from the 55 seconds backwards, as described in 
section i^z^'^)- Keeping your nail just before the watch seconds 
hand, as you say " Naught" (and the clock hand touches 60) 
you begin to count the beats till the watch hand reaches the 
next mark, then hold your nail there till you have fully satisfied 
yourself of the number of that mark. If you counted 2 beats 
from the " Naught" to the next mark on the watch, that will 
show that your previous count of 3 beats from the watch mark 
to the next clock mark was correct, for 34-2 = 5, the number 
of beats per second. Therefore, if that mark was the 13th sec- 
ond, your watch would be i2-| seconds fast. Some workmen 
omit this counting of the beats the last time, and on saying 
" Naught" hold the nail still. The last previous mark gives the 
number of seconds, to which they add the number of beats 
before counted. But the result is more certain by counting 
twice, as just described. 

(373-) The same on an imperfect dial. — In that case, it will be 
necessary to take the time on the clock dial when the watch 
seconds-hand strikes its 60, as described in section (369). Sup- 
pose the regulator hand stood at 44 seconds, and there were two 
beats after that and before the watch hand touched 60, your 
watch seconds-hand is i6|- seconds fast of the clock hand. 
II 



i62 THE WATCH ADJUSTER'S MANUAL. 

(374.) Attention should be paid to the fact that sections (368, 
369,) and (371, 373) refer to cases where the watch seconds- 
hand is on the right or left side of the 60 when the time is com- 
pared, i.e.^ it is ahead or behind that of the clock. But the 
watch itself may be fast, (say, 45 seconds fast,) although its 
stconds-ha?id is on the left side of the 60, or it may be slow 
(say, 45 seconds slow) while its seconds-/^«;z^ is at the right of 
the 60. The rules are simply for securing an accurate compari- 
son of time when the hands occupy certain positions. 

(375.) Co7nparing times with the aid of an assistant. — Many 
workmen find it almost impossible to compare a watch with the 
regulator as described, with any certainty, within 2 or 3 seconds. 
Such will be able to follow the directions given if they will have 
some assistant call out the seconds on the regulator while they 
keep their attention fixed on the watch. Everything being 
ready, the assistant begins at the 55th second and calls "Five — 
Four — Three — Two — One — Naught," pronouncing each number 
exactly at the instant the regulator hand strikes each second, and 
the " Naught" exactly at the 60. Any bright boy can do this 
properly after a little training, and the workman should then be 
able to count the beats on the watch and time it to \ second. 
By this method, he knows exactly where the regulator hand is, 
and has constant warning of its approach to the 60. It is 
equally useful in helping to set the watch exact with the clock. 

(376.) Sa7?ie, whe?i the watch hand is at the 60. — When it is 
required to compare the time when the seconds-hand of the 
watch is at its 60, which we have seen is sometimes necessary, 
the workman begins at the 50th second and calls out " Now" at 
each second on the watch, till the 54th, saying that very loudly. 
The assistant begins at the next second on the clock, (being 
warned by the loud call,) and calls out the numbers backward 
(as in the preceding section), taking notice of the number of the 
second on the clock when he says " Naught." At the same call 
the workman begins to count the beats on the watch, between 
the call and the arrival of the hand of his watch at the 60. If 
he counted 3 beats, and the assistant reported 22 seconds at the 
"Naught," there would be 22-| seconds difference between the 
watch and the clock, if the clock hand was ahead. If it was 
behind the watch hand, /.<?., between the 30 and 60, say, at the 
44th second, that would of course make the difference i6|- 
seconds. 

(377.) Rate booJz.—^\i^Vi we are merely regulating, we correct 
the observed error each time, without any special reference to 
what the watch has done before. But in rating, we make some 



THE WATCH ADJUSTER' S MANUAL. 163 

record of its performance at each observation, and the proper 
correction is decided upon after considering its errors at previ- 
ous times, or under different conditions. A rate book is there- 
fore a necessity in rating watches, (or, at least, rate sheets of 
paper,) and in it should be recorded the exact details of each 
observation, for future reference. The owner's name, and a 
brief statement of the kind of watch, and its number, should 
head the page, which should be ruled off in columns to suit the 
tests or observations made. In all cases, the first column 
should give the date of the observation ; it is also advisable to 
add a column for the hour, as it may often help to trace out 
some error, or, at least, to explain the circumstances. The 
next column gives the observed difference between the watch 
and the regulator, preceded by the mark -|- to indicate a gain, 
and — for a loss; it is well to add a column for the number of 
days that have elapsed since the last observation. The next 
column gives the error per day, since it was last regulated and 
set, ascertained by comparing the difference from the clock this 
time, and the last previous time, and dividing the difference by 
the number of days, (col. 4.) Column 6 states whether the 
watch was then regulated (R), or set to time (S), or both. 
If you are doing thorough first-class work, you should add 
column 7, showing the mean daily rate \z^Z)'> ^'^d the 
number of days during which it averaged that amount should 
be stated in column 8. Column 9 gives the temperature 
(or average) since the last observation, or if the watch has 
been exposed to the sun, or any unusual heat or cold. Column 
10 gives the position, in the shop; or states if it is being 
carried, or anything special which has happened to it since 
the last observation, or if any alteration of the mechanism was 
made. 

(378.) It is important that all the facts which affect the rate 
should be known, and as the workman cannot be expected to 
remember them, they must of course be recorded. In noting, 
mark the hours by the letter "h," or simply by the number, the 
minutes by one dash after the number, and the seconds by two 
dashes. Thus, 10 minutes and 45 seconds after 9 o'clock in the 
forenoon would be written " 9 — 10' — 45", A.M." Always mark 
the time with A. M. or P. M., to prevent any possibility of mis- 
take, for you might compare times at 9 o'clock either in the 
morning or evening. In the observatories, they count up to 
24 o'clock, from midnight to midnight, and therefore do not use 
A.M. or P. M. to designate the hour, but watchmakers follow 
the usual custom. 



164 



THE WATCH ADJUSTER'S MANUAL. 



(379.) A page of the rate book, or of the rate sheet, would 
be ruled off about as follows: — 

JOHN W. JONES. 
Gold English Lever. Dent No. 25,502. 



Date. 


Difference from 
Regulator. 


Daily 
Error. 




Mean E 
Rate. 


ally 
Tn 


'4 


Positionand 
other con- 










ditions af- 


1894. 


Hour, 
h. m. 


m. s. 


Days. 






Days. 


88° 


fecting the 
rate. 


Mch. 29 


10,10' A.M. 


+ I' 27|" 


3 


+ 29r„ 


R,S, 


+ 43F' 


5 


Hanging. 


- 31 


II. 15' A.M. 


+ 53^' 


2 


+ 26.3" 


R,S, 


+ 38.5" 


7 


85^ 


' ' 


Apl. 3 


10.30' A.M. 


+ 36" 


3 


+ 12" 


R.S. 


+ 17I" 


5 


70^ 


Let out 
hairspring. 


Apl. 4 


10.15' A.M. 


-14" 


I 


-14" 


R.S, 


+ i2-y' 


6 


75' 


Hanging, 


Apl. 6 


10.15' A.M. 


- 511" 


2 


- 251" 


R.S, 






So- 


Carried in 
pocket. 


Apl. 9 


10,30' A.M 


- 2lf" 


3 


-7r 


R.S. 


+ 0.2" 


II 




Carried. 



(380.) The first six columns, and the last one, are really neces- 
sary. The other three can be dispensed with, although they 
are useful when doing fine work. The form given is adapted 
for regular rating or regulating. For adjustment tests, the rate 
sheet should be ruled off to suit the work. The watches should 
be hung on the rack in the same order that they come in the 
rating book, so that it will not be necessary to spend any time 
in looking up the right page. It will take but a moment to 
write down the items. You would want to make some memo- 
randum of the error, even if you kept no rate book — and by 
having it in a permanent form it will be a valuable record, from 
which you may learn some very practical facts. For instance, 
it would help you to detect an acceleration in the rate. 

(381.) Acceleration of rate. — In regulating a new hair spring, 
allowance must be made for a peculiar action which has been 
noticed in newly made hardened and tempered springs, (23,) 
viz,, that they accelerate on their rate for the first few weeks or 
months, and then, having attained their highest degree of plia- 
bility and elastic force, become constant. For this reason, the 
watch or chronometer cannot be regulated immediately after 
fitting such a spring, to maintain a perfectly uniform rate for a 
long period. But after bringing it closely to time, the mean- 
time screws may be drawn out to cause a loss of a few seconds 
per day, (two to five, generally,) by which means it will take 
nearly a correct rate after the accelerating process is ended. 



THE WATCH ADJUSTER' S MANUAL. 165 

The amount is, of course, a matter of guess work, but a 
moderate alteration will make the final rate nearer correct than 
if there had been no change. Where the precise permanent rate 
must be known, as in marine chronometers, whose error of rate 
is a vital element in the calculation of longitudes, etc., it is 
necessary to await the completion of this acceleration before a 
trustworthy rate can be got. Cases occasionally occur where 
the spring continues to change for several years, but generally 
they do so only for a few months. 

(382.) Cause of the error, — Some attribute this to the spring, 
others to the balance. But it has been found that if a spring 
has been bent out of shape and then restored, it will accelerate 
like a new spring; also, that a balance which has been similarly 
injured will accelerate. It would seem probable, therefore, that 
the action was due to the metal of either the spring or the bal- 
ance, or of both, acquiring its permanent condition, or at least 
acquiring a condition different from the original one. The fact 
that bending will cause the acceleration to occur again, would 
seem to confirm this. The practical lesson to be derived is, 
that one should be very careful in handling both springs and 
balances, or he may render it impossible for him to obtain a 
uniform and permanent rate for the watch. It is claimed that 
a spring hardened at a low temperature is not so liable to gain 
as one hardened at a higher temperature. But it does not gain 
in proportion to its hardness. A very hard spring is no more 
difficult to time than a softer one, is more stable and lasting, 
and the acceleration disappears after a short time, as before stat- 
ed. Palladium hair springs accelerate somewhat less than steel, 
and no allowance need be made in the rating for the accelera- 
tion. 

(383.) Loss of rate in soft springs. — While a hardened and 
tempered spring will gain on its rate, one that is not hardened 
and tempered loses. Not having its molecular condition changed 
by fire-hardening, but being merely stiffened by wire-drawing 
and rolling, the constant bending to and fro of the soft metal 
probably extends or gradually lengthens it, and may be con- 
sidered as a deterioration of condition, as it generally continues 
to lose until it finally becomes "exhausted" and useless. In 
rating fine watches with such springs, allowance must be made 
for this. After getting as close a rate as possible while in the 
shop, then cause the spring to gain a certain amount — varying 
from 4 to 10 seconds daily, according to the watch, which will 
bring its permanent rate nearly correct. But it is better to fire- 
harden the spring, as directed in section (263), and avoid this. 



l66 THE WATCH ADJUSTER'S MANUAL. 

trouble. Of course, in low grade watches, this error is less 
important. 

(384.) Middle temperature error. — In compensating for heat 
and cold with the compensation balance of ordinary construc- 
tion, if they are correctly adjusted for the two extremes, they 
will gain at the mean temperature 2 seconds per day, on an 
average, in marine chronometers. In pocket watches, this error 
may sometimes be as much as half a minute per day; but when 
it exceeds a few seconds it must be considered as evidence of 
either a poor adjustment or an imperfect balance. On the other 
hand, if the watch is correctly rated at the mean temperature, 
it will lose as the temperature rises or falls, and will lose 2 
seconds daily (in chronometers) at the extremes. It is cus- 
tomary to rate the watch or pocket chronometer at the temper- 
ature in which it will ordinarily be kept, and locate the error in 
the other temperatures, to which it will only seldom be exposed. 
See section (766), in the Adjustment for temperatures. With 
marine chronometers, it is customary to compensate so that the 
rate will be correct at the two extremes of heat and cold, to 
which it will be exposed, and it will then gain as the temper- 
ature approaches the mean, and lose as it goes outside of the 
extremes. The loss is stated as \\ seconds in 24 hours for a 
temperature 15° above or below the extremes for which the 
watch is adjusted. The above shows that in closely rating a 
chronometer or fine watch, it is necessary to know (approxi- 
mately, at least,) whether it has been adjusted to time at the 
mean or the extremes, and at what temperatures. This can be 
found by testing. But if not known, it will generally be safe 
to assume that it has been adjusted at about 45° and 90°, and 
make the proper allowance for a middle temperature error at 
65° or 70°, Fahr. 

(385.) Duration of trials. — A close rating requires consider- 
able time, as, after the first few days have shown that the watch 
is running closely, the trials have to be for longer times in order 
to get trustworthy results. Even in observatories, (as at Yale,) 
where they have apparatus for detecting errors to yiir second, 
watches which are entered for first-class certificates are tested 
for 45 days; second class, 29 days, and third class, 16 days. 
The first and second class trials are for temperatures and 
positions, the third class for positions only. The Greenwich 
observatory trials are much longer and more severe, being 
mainly for marine chronometers. The trials last 29 weeks, and 
the temperature range is from 37° to 103° Fahr. 

, {i^d.^ Testing the isochronism. — But the watchmaker should in 



THE WATCH ADJUSTER'S MANUAL. 167 

all cases make an additional trial for isochronism, />., see 
whether the rate is the same in the long and the short arcs of 
vibration. If not, as already stated, the watch cannot be rated 
except at the same hour each day. Such a fault is a vital one, 
and should not be allowed to pass in a first-rate watch. The 
method of making such a test is fully explained under the head 
of Isochronal Adjustment. 

(387.) Errors in the rate. — In the trials at the Kew observa- 
tory, (class A,) change of temperature must affect the daily 
rate less than \ second for each degree, Fahrenheit. The daily 
rate must not exceed 10 seconds. The mean difference of 
daily rate between any two succeeding days, during each period 
of comparison, (5 days,) must not exceed 2 seconds. The 
difference of mean daily rate between pendant up (hanging) and 
dial up (lying down) must not exceed 5 seconds. The differ- 
ence of mean daily rate (of a 5 day period) between pendant up 
and any other position must not exceed 10 seconds. In the 
second grade (B) trials, which are for ordinary deck watches 
for ships, the position tests are limited to pendant up and dial 
up, and the variation must not exceed 2 seconds in either 
position, nor exceed 10 seconds between hanging up and lying 
down. Temperature limit as before. Class C is for positions 
only, limits as in class B. 

(388.) Excellence marks. — In class A, marks, showing the 
exact excellence of the performance, are given in the certifi- 
cates. They are calculated as follows: If the error of the 
watches is just the amount stated as the limit, it gets no marks, 
but barely passes, with a certificate. In the trials for daily 
rate, the limit, 10 seconds, is divided into 40 parts, of .25 sec- 
ond each; for each .25 second less than 10 seconds, the watch 
gets I mark, and, of course, if its rate was perfect, it would get 40 
marks, which would indicate no error at all. The position limit 
of 2 seconds is divided into 40 parts, of .05 second each, and 
each .05 second that the error is less than the limit gains i 
mark. The temperature error is divided into 20 parts, of .015 
second each, and each .015 second that the error is within the 
limits gets i mark. If the watch got 100 marks, it would indi- 
cate perfection. If the watch gets 25 marks for mean difference 
of daily rate, and the other errors noted in section (387) for 
daily rate, positions and temperatures, are less than half the 
limited amounts, it is marked " especially good" in the certifi- 
cate. The foregoing details will show the workman what per- 
formance is considered good, and what errors are allowed to 
pass by good adjusters. 



PART FIFTH. 



SPECIAL AND ''NATURAL'' COMPEN- 

SA TIONS, 



CHAPTER XXIV. 

The Four Principal Escapements. 

(389.) Require different treatment. — As will be seen from the 
following chapters, the different escapements require entirely 
different procedures, as regards the length of the hair springs, 
the number and openness of the coils, the mode of pinning them 
in complete or fractional coils, in the size and weight of the 
balance, the size and closeness of fitting for its pivots, the 
strength of the motive force, the mode of oiling and the kind of 
oil, and numerous other vital points of detail, besides the 
proper design and construction of the escapement itself. Some 
require isochronous hair springs and compensated balances, and 
others are better off without them. These are some of the 
points in which each escapement needs special treatment adapted 
to its peculiarities and requirements, but the details on such 
points are not needed in the general directions, and if inserted 
there would only encumber them and confuse the inexperienced 
workman who was in quest of information. 

(390.) New departure. — I have therefore thought it desirable 
to take an entirely new departure in the manner of treating the 
subjects of timing and the adjustments, to deal with each 
escapement by itself, so far as it needs special handling, and to 
separately explain the merits and the weaknesses of each, its 
peculiarities and requirements, what it can do, and what it is 
unsuitable for, without being mixed up with general directions 
and rules which do not apply to it, and which if followed would 
be detrimental to its performance. Only in that way can the 
workman obtain a clear and correct idea of the nature and 
needs of each escapement. 

My task has been to sift out from the mass of different and 
contradictory opinions, experiences and results before the trade, 
published and unpublished, those which relate to each different 



THE WATCH ADJUSTER' S MANUAL. 169 

kind of escapement, and to state the best method to follow 
with each one of them, and in different circumstances. That 
has never been done before, and to do it has involved ten-fold 
more labor and time than to have merely stated either my own 
experiences and opinions, or those generally held by the practi- 
cal men in the trade. 

(391.) Merits of different escapeinents. — Charles Frodsham has 
well stated the truth about the different escapements as follows: 

" The true seat of the time-keeping principle in every watch 
or chronometer resides in the union of a perfectly hardened 
tempered balance-spring and a perfect compensation balance, 
the weight and diameter of the balance being in just proportion 
to the motive force. The special value of particular escape- 
ments and of escapements in general is very much overestimated ; 
for, when each of the three well-established escapements, the 
Arnold for chronometers, the duplex and lever for watches, are 
equally well made, and tried with the same balance and balance- 
spring, the result of their performance is not so marked as is 
generally believed, nor is the superiority of the one escapement 
over the other so evident as many persons have been led to 
imagine. The Arnold escapement is undoubtedly the most 
accurate and the most proper escapement for marine chronome- 
ters. The perfection of every watch or chronometer lies in the 
talent and ability of the watchmaker to combine the several 
parts into one harmonious whole." 

(392.) While that is undoubtedly true so far as regards the 
principle of the escapement, in practice that escapement is pre- 
ferable in which the proper harmonious relation of the parts can 
be most easily and surely secured by the maker, and retained or 
restored by the repairer, and whose performance is least affected 
by imperfections and injuries. Judged on that basis, the chro- 
nometer escapement is very inferior for use in pocket watches. 
Frodsham himself adds that: " The talent to produce a first-rate 
reliable chronometer for the pocket falls to the lot of few." It 
is the special object of Part V to enable the workman to "com- 
bine the several parts into one harmonious whole," and he will 
do well to carefully note and observe every detail of the instruc- 
tions given. 

(393-) The difference in the escapements. — The cylinder and the 
duplex are frictional escapements, in which the escape-wheel 
teeth rest against the axis of the balance and directly influence its 
movements. The lever and the chronometer are detached escape- 
ments, — the movement of the balance being disconnected from 
the influence of the escapement or the train during the greater 



170 THE WATCH ADJUSTER'S MANUAL. 

part of its vibrations. These differences are radical, both in 
their nature and in the consequences involved. By taking proper 
advantage of them, the two former escapements have what is 
termed "natural compensation,"/.^., they can be so arranged 
as to compensate for differences in the motive force, the arc of 
vibration, the frictions, the temperature, etc., by the mechanical 
action of the escapement alone; while the two latter require to 
be compensated by special means and adjustments. The direc- 
tions for " adjusting" watches therefore apply as a general rule 
only to the detached escapements. The requirements of the 
" natural compensations" will be given in connection with the 
two frictional escapements. 

(394.) Mechanical condition of the escapement. — Aside from the 
matter of compensation, there are obviously many details of 
proportion, arrangement and condition of the various parts of 
the escapements, which must be carefully attended to in order 
to secure a proper action of the mechanism. Many details 
regarding the escapement and the train are therefore given, 
because in the frictional escapements they directly affect the 
timing of the watch, while in the detached escapements they 
do so indirectly, by varying the effective motive force, the man- 
ner of giving the impulse, the resistances during the temporary 
connection of the balance with the train, etc. But in the latter 
cases, the motion of the balance is cofnparatively independent of 
the condition of the train and the proportions of the escape- 
ment — hence only such details are given as do affect the timing 
or the movement and action of the balance. All faults and 
imperfections beyond those limits belong more properly to the 
watchmaker's or repairer's department, and cannot be treated 
here. 

(395.) Adjusting the different escapements. — The mechanical 
manipulations of the escapement to obtain a correct compensa- 
tion are as truly an *' adjustment" as if the same result had been 
obtained by manipulating the balance or the balance spring. 
The chapter on the cylinder and the duplex escapements con- 
tains all the directions for adjusting them as perfectly as it can 
be done ; while the chapters on the lever and the chronometer es- 
capements give all the special technical details which influence the 
timing of each, and the reader is then referred to the more gen- 
eral parts of the book, where he will find the subjects of 
springing, timing and adjusting treated more fully and 
practically, it is thought, than has ever been done before. 
As the book is not based upon the studies and opinions of any 
one workman, however eminent, but upon the results and ex- 



THE WATCH ADJUSTER'S MANUAL. 171 

periences of all practical men everywhere, so far as publicly 
known, we believe that the reader will find it complete, ac- 
curate, practically useful, and worthy of its title, the Adjuster's 
Manual. 



CHAPTER XXV. 
Cylinder Escapement Watches. 

(396.) Ge?ieral characteristics. — The cylinder escapeme?tt^ also 
called lepine and horizontal.^ is so well known that it will be 
unnecessary to describe its principle or action, further than con- 
cerns the springer and adjuster. It needs neither the isochro- 
nal hair spring nor the compensated balance, having what is 
termed " natural compensation" for temperature and variations 
in motive force. The good performance of this escapement 
depends upon a correct proportion between the parts of the 
escapement, the strength of the motive force, and the size and 
weight of the balance. It cannot be isochronized unless this 
proportion exists. But if it does, this escapement is less affected 
by changes in the strength of the motive force than any other 
which is used in watches. It can also be so closely compensated 
for temperatures, isochronism and position, by very simple 
means, as to answer all ordinary requirements for a low-priced 
watch. A well-made cylinder escapement therefore needs but 
little adjustment in order to make it a fairly good timekeeper, 
and the directions given in this chapter will suffice for that pur- 
pose, by indicating what the correct proportion should be, the 
effect of deviation therefrom, and the proper remedy. 

(397.) The hair spring. — From 8 to 12 coils are used, many 
makers preferring from 8 to 10, as being more suitable for a 
frictional escapement; others prefer 12. They are pinned 
nearly half a turn short of even turns, as they are found to act 
better when so pinned, being short and the balance vibrations 
small. They generally have 18,000 vibrations per hour. Small 
watches, with very light mainsprings, being very sensitive to 
shaking, change of temperature, etc., are made to give 19,000 
to 21,000 vibrations per hour, and very small watches (from 9 
to 6 lines in diameter) have sometimes as many as 24,000 per 
hour. Even watches of ordinary size, (13 to 20 lines in diame- 
ter,) when to be exposed to severe shaking, etc., are made to 
give 19,000 vibrations per hour. The standard arc of vibration 
is 270°, or three-quarters of a turn. 

(398.) The balance. — The good performance of this escape- 



172 THE WATCH ADJUSTER' S MANUAL. 

ment depends largely on the proper weight and diameter of the 
balance. If the balance is not correct, it will be impossible to 
make the long and short vibrations equal by changing the hair 
spring. If the watch gains when the motive force is increased, 
the balance is too small and heavy. Some improvement would 
be secured by making the balance lighter and fitting a weaker 
hair spring to suit, but the light balance would be more easily 
affected by differences in the motive force, in the temperature, 
oil thickening by cold, shaking and jarring, making it unsteady 
and unreliable. The proper change is to make the balance both 
lighter and larger, with a hair spring to suit ; then the perform- 
ance is steadier and better. 

(399.) A balance too light is too sensitive to variations in the 
motive force, frictions, change in the condition of the oil, etc. 
One too heavy is difficult to time, especially in positions. If 
regulated hanging up, it will gain when lying down ; if regu- 
lated lying down, it will lose when hanging. This difference is 
due to the difference in the frictions in the two positions, and it 
increases as the balance is heavier. The friction of the pivots 
must be equalized, or a stronger and more suitable hair spring 
used, if the balance cannot be replaced. But when a rather 
small cylinder and escape wheel are used, the balance may safely 
be smaller and heavier, and this combination or proportion is 
considered to give the best performance which this escapement 
is capable of. 

(400.) The escapement. — The usual rule is that the escape 
wheel should be half the diameter of the balance or a trifle less. 
Of course, this rule works both ways, and may serve as a guide 
to the proper size of the balance. Be sure that the teeth clear 
the slot in its cock when at their highest point of end shake, 
and that there is no oil or dirt in the slot to clog it; also that 
the teeth clear the 4th wheel pinion, and that the extremities of 
the arms carrying the teeth do not rub on the top of 4th wheel, 
when that is at its highest position. 

(401.) Freedom in cylinder. — See that there is freedom both 
when the tooth is inside and outside of the cylinder. In doubt- 
ful cases, hold the balance still and test each tooth, in both 
positions. The teeth should also be free from the cylinder 
plugs above and below them. If there is freedom when the 
tooth is outside, the cylinder shell may be too thick; the wheel 
may pitch too deeply, i.e., the wheel and cylinder planted too 
close together; the cylinder too small; the escape-wheel teeth 
too long, or not equal. It is customary to allow more freedom 
inside than outside, to prevent the heel of the teeth from rub- 



THE WATCH ADJUSTER' S MANUAL. 173 

bing, in case the pitching is too deep. The easiest remedy is 
to " top" the teeth. See Rapping, (411.) If there is freedom 
inside, but none outside, the cylinder is probably too large, and 
if the teeth are so formed that " topping" will not cure it, a 
smaller cylinder should be fitted. 

(402.) The cylinde}'. — As a general rule the cylinder should be 
•i- the diameter of the escape wheel, or the wheel diameter mul- 
tiplied by . 115. The thickness of the shell should be about \ of 
the length of the tooth, /.^. , of the incline or outside. The 
shell is cut away for the teeth, not quite half through, its acting 
part being about 200° of a circle. The two edges or lips of the 
acting part are called the enteriiig Up and the exit lip. The 
former is rounded from both sides, the latter from the inside 
only, making a sort of inclined plane for the teeth. The lips 
should be smooth, well polished, and free from rust, and the 
shell both inside and outside free from pitting or cutting. The 
slot is cut away so that only \ of the circle remains. See 
Recoil, (412). 

(403.) Improper cylinder. — When the cylinder is too large, the 
friction is increased and the retarding force becomes excessive, 
the vibrations become sluggish and smaller, and the watch is 
difficult to regulate. Large cylinders with large escape wheels 
require stronger mainsprings and lighter balances, and are more 
sensitive to thickening of the oil and other retarding influences. 
When the cylinder is too small (relatively to other parts of the 
escapement), the teeth will be too close in the cylinder, and the 
balance vibrations will be weak, because the leverage is too 
short. If the escape-wheel teeth are naturally short enough for 
the cylinder, (containing a high number of teeth,) the incline 
on the teeth must be more steep, and the mainspring stronger, 
in order to get a sufficient impulse for the balance — both objec- 
tionable features. 

(404.) In beat. — W^hen the balance is at rest and free from 
any pressure of the escape-wheel teeth, the hair-spring stud 
should be in line with the two lips of the cylinder. To test the 
beat, notice the dot in the edge of the balance and the three 
dots on the watch plate. When the watch is made, the dot in 
the balance rim is set just opposite the middle dot on the plate, 
and the dots on each side of that indicate the extent of the 
impulse lift. If the parts have not been disarranged, the beat 
can be tested by them. Put a pegwood point against the rim of 
the fourth wheel, and hold it, cutting off the motive force from 
the escape wheel. When the balance is perfectly free and still, 
the dot on the rim should stand opposite the middle dot on the 



174 THE WATCH ADJUSTER'S MANUAL. 

plate. Then press the pegwood forward and cause the balance 
to move slowly each way till the tooth escapes. The distance 
it moves from the point of rest should be the same in each 
direction, and at the end of each movement the dot in the rim 
should be opposite the outside dot on the plate. If the dot on 
the rim is not in the center of these two extreme positions, move 
the hair-spring collet to carry the stud towards the side having 
the smallest motion. When it is corrected the stud should hang 
in line between the dot on the rim and the upper cylinder pivot, 
both when in the watch and when the balance and hair spring 
are out. When the watch has been worked at and the dots are 
disarranged, make a new dot or mark on the balance rim, and 
proceed as directed in section (288). 

(405.) The foregoing sections give the proper and normal 
positions, but in some cases the spring is purposely put out of 
center or otherwise displaced, for timing purposes (277, 694). 
Hence it is a safe rule when merely cleaning, or repairing some 
part which does not involve the adjustments nor " putting in 
perfect order," to put evci-ything exactly as you found it^ (Chapter 
I,) unless you are certain it is wrong. 

(406.) The bajiking. — The watch being in beat, as described, 
when the balance is at rest and free the banking pin in its rim 
should stand exactly opposite to the banking stud^ which is a pin 
fixed in the balance cock at the other side of the balance. This 
can generally be tested by " sighting" across the balance from 
the pin to the stud. A line from the pin through the cylinder 
pivot should strike the center of the stud. Furthermore, the 
position of the banking pin is generally a quarter of a circle 
distant from the beat-dot in the rim, (404) i.e.^ a line across the 
balance, from the dot through the center, would be perpendicu- 
lar to a similar line from the pin, through the center. Conse- 
quently, the dot should be midway between the banking pin and 
the banking stud. The banking is very important, because the 
balance must not vibrate more than one turn, i.e.^ half a turn 
each way from the point of rest, as that is all that the half-shell 
of the cylinder can allow. If the motion exceeds that amount, 
on either side, we shall have overbanking (408), and perhaps 
rapping (411). 

(407.) See that the banking pin cannot miss the stud in any 
position of the watch, (from changes due to the end-shake of 
the cylinder,) and that it is long enough to hit the stud properly. 
If the pin is a little short, and liable to get over on the end of 
the stud, arrange the stud nearer the rim of the balance, (but 
not too close,) or put in a longer pin. Also see that there is 



THE WATCH ADJUSTER'S MANUAL. 175 

no incline on the stud where the pin strikes it, tending to cause 
the pin to rise over or under it, and wedge or stick there, instead 
of striking the stud fairly and squarely. The pin must safely 
clear the fourth wheel pinion or arbor, the balance cock, the 
case, etc. The banking pin and stud, as well as the edge of the 
balance and the arms of the escape-wheel teeth, should be clean, 
free from oil or other sticky matter, and dry, otherwise the 
watch may run irregularly or stop. 

(408.) Overbanking. — When the tooth drops onto the cylinder 
the balance continues its vibration to the end, or till stopped by 
the banking pin hitting the stud, and then returns. But if the 
banking pin is not properly placed and allows the balance to go 
too far, the point of the tooth slips over the wrong lip of the 
cylinder and catches, so that the balance is held fast and cannot 
get back. This is called overba?iktng. To release the balance, 
move the escape-wheel tooth back a little, just enough to let 
the lip get before the point of the tooth, then let the wheel go. 
In rare cases, this is caused by the lips of the cylinder being 
worn or cut, or having been worked at, till the shell is too 
small, i.e.^ the part remaining is barely half a circle, or less 
than 200°. 

(409.) Ronedy for overbanking. — In the former case, the teeth 
may sometimes be caused to run on the sound part of the lips 
above or below the cut; in the other case the proper remedy is 
a new cylinder. But if the vibrations are small, it is possible 
to prevent overbanking by putting in another stud at one side of 
the old one, to prevent the balance coming around far enough 
to catch. If it catches on both sides, two new studs will be 
needed. This course may be unobjectionable unless there is 
danger of '' rapping" (411). 

(410.) To test for overbanking^ move the balance around each 
way till the pin stands against the stud, (the watch being 
wound,) to see if it catches. If it does, the vibrations are not 
equal on the two sides, (the banking pin and stud not in the 
same diametrical line), or the balance is not properly staked on 
the cylinder, so that the banking pin is not midway between the 
two lips, (the two diametrical lines are not perpendicular, as 
described in section (406), on the banking,) or the lips have 
been so worn or changed that the banking pin is not midway 
between the two dots (404) showing the extents of the lifts. 

(411.) Rapping. — If the vibrations are so large that the bank- 
ing pin frequently hits the stud, great irregularity in time is the 
result. It may be cured by a weaker mainspring or a heavier 
balance. If these do not stop the rapping, the impulse may 



176 THE WA TCH ADJUSTER'S MANUAL. 

be lessened by " topping" the escape wheel. Arrange it in the 
turns, and very carefully and evenly take off the heels of the 
teeth, either by grinding with an oilstone slip or by polishing 
with a burnisher, islake but little change, and try it in the 
watch, to avoid overdoing it. Test the smoothness of both the 
points and the heels; they should not feel rough and scratch on 
the finger-nail; if they do, they are either rough or too pointed 
and sharp. This alteration shortens the length of the incline 
on the teeth, reduces the lift and the impulse, and increases the 
drops and freedom. 

(412.) Recoil. — When the banking is properly adjusted, give 
the balance a large vibration, by pressure on the center wheel, to 
see if the escape wheel recoils while running. That is caused 
by the lip hitting against the front of the arm of the tooth. It 
can also be tested by moving the balance back till the banking 
pin hits the stud, then try if there is freedom between the lip and 
the arms of the teeth. If they touch, the passage can be cut a 
little deeper with a sapphire file or a steel slip and oil-stone 
dust. The exit lip of the cylinder should pass over the arm of 
the wheel without touching or coming so near together that the 
oil can run from the lip to the arm of the tooth, and cause foul- 
ing with some other part. 

(413.) Setting. — If the watch sets and stops, especially when 
the oil is thickened by cold, the incline of the escape-wheel 
teeth is probably too high, and a larger cylinder or a stronger 
motive force may be required. 

(414.) £s cape -70 he el pinions. — If the diameter of this pinion 
is too large relatively to the diameter of the escape wheel, the 
balance will not move with sufficient freedom, but will seem 
constrained. This appearance may direct attention to the cause 
of the fault. With a large pinion, the fourth wheel depthing 
must be very correct, as any errors in the depthing will show in 
the action of the escapement. The escape wheel will probably 
have too much force for the balance. 

(415.) To straighte?i a cylinder pivot. — It is very essential that 
the cylinder shall revolve concentrically, and the pivots should 
always be straight and in good condition. To straighten a 
bent pivot, take a pivot " bush" or bouchon, fit it over the bent 
pivot, and bring it up into line with the axis of the cylinder. 
If you have no bush, a hole drilled truly in the center of a hard 
brass wire may be used. If the hole is drilled correctly and the 
wire is straight, its length makes it an easy matter to get it 
vertical, and when the wire is vertical, the pivot will be verti- 
cal, too. 



THE WATCH ADJUSTER'S MANUAL. 177 

(416.) Natural compensation for heat and cold. — As oil is used 
on the impulse planes or rubbing surfaces of a frictional escape- 
ment, and the pivots are also comparatively large, the con- 
dition of the oil becomes an important factor in the running, 
and gives the cylinder escapement a sort of natural compensa- 
tion for changes of temperature. In vi^arm weather, the oil is 
thin, and there is a quicker action of the escapement; in cold, 
the oil becomes thicker, produces a more sluggish action of the 
balance, and counteracts the effects of cold upon the hair spring 
and balance. In order to secure a sufficient compensation in 
this way, the oil should evidently not be too liquid, and should 
become considerably thicker by cold. Hence the modern oils 
which do not thicken in cold are not so suitable for cylinders, 
although excellent for detached escapements. Another requi- 
site is that the hair spring should not be too long, as the cor- 
recting effects are more marked in short springs, and insufficient 
in those which are too long. The spring should therefore be 
shortened to increase these effects, and lengthened to lessen them. 

(417.) Natural compensation for variations in the motive force. — 
The cylinder escapement also has a very efficient compensation 
for changes in the motive force, as, the greater that force is, 
the greater is the pressure of the tooth on the cylinder to 
restrain its motion and keep the balance vibrations equal. This 
compensation it possesses in a greater degree than any other, 
and it is therefore specially adapted for going-barrel watches of 
a grade too low to admit of special adjustments. It is neces- 
sary, however, that there be the correct proportion between the 
parts of the escapement already spoken of. If the cylinder is 
too large, for example, the friction of the tooth upon it is so 
great that the effect is too much for a correct compensation for 
changes of motive force, and the watch cannot be regulated. 

(418.) Natural isochro7ial compensation. — The compensation by 
friction described in the preceding section, which keeps the bal- 
ance vibrations of substantially the same extent, combined with 
the compensation for the effects of heat and cold on the hair 
spring and balance, virtually constitute a natural isochronal 
adjustment, when correct. It is only correct, however, when 
there is the correct proportion between the parts of the escape- 
ment, and when all the influences at work combine to balance 
and neutralize each other, keeping the vibrations uniform, and 
in reality doing away with the necessity for isochronal adjust- 
ment. 

(419.) Frictional adjustment for isochronism. — If desired, the 
isochronism can be adjusted and perfected by varying the rela- 
12 



178 THE WA TCH ADJUSTER'S MANUAL. 

tive amounts of the escapement friction and the arcs of vibra- 
tion, as described in section (570). But it should be remembered 
that a cylinder watch cannot be isochronized unless there is the 
correct proportion between the weight and diameter of the bal- 
ance, the size of the cylinder, and the motive power. And 
further, the opening of the cylinder and the impulse angle of 
the escape-wheel teeth must be such as to give, if not the best, 
at least fully satisfactory, performance. 

(420.) lsochro7iizing by the regulator pins. — In watches which 
have but few coils in the hair spring, and they are well separated 
from each other, considerable improvement in the isochronal 
action can often be obtained by opening or closing the regulator 
pins, as directed in sections (585) to (588). 

(421.) I sochronizing by the balance. — When the weight of the 
balance is too small for a correct proportion to the rest of the 
escapement, it can be made heavier as directed in sections {^^zZi 
334). If too heavy, the balance (if a plain one) can be gripped 
by the edge in a lathe chuck, with the under side out, and a 
very little cut out in a central groove around the rim. Then 
poise and test it. This is easier than fitting a lighter balance, 
but should not be done when the watch needs a balance which 
is both lighter and smaller. In a screw balance, the screws can 
be altered as required. 

(422.) Timing in positions. — The watch being closely regulated 
in a horizontal position, (dial up,) try it hanging up. If it 
gains when hanging, take a little off the bottom of the balance; 
if it loses when hung up, take a little off the top. What is here 
meant by the bottom and top, is that part of the rim which is 
lowest or uppermost when the watch is in the hanging position, 
and the balance at rest, free from the motive force. A vertical 
line through the pivot or the center of the balance will pass 
through the top and bottom points of the rim. The metal 
should be filed from the under side of the rim and on the inner 
edge. Take off but very little, testing the effect frequently, as 
it puts the balance out of poise, and too much change should 
not be made. It should only be practiced on low grade watches, 
and which do not vibrate over one turn. It is not suitable for 
watches which are carried in the pocket loosely, so that they 
may turn and change their positions, as the effect produced would 
be the reverse of the one desired if the watch should be worn 
with the other edge up. Of course, the same alteration can be 
made on screw balances by running the screws out on the side 
to be made heavier, and vice versa, or by filing off their heads, 
or by removing a screw from one side and not from the other, 



THE WATCH ADJUSTERS MANUAL. 179 

or by removing it from one side and inserting it in the other 
side at a point exactly opposite. 

(423.) To test if the bala7tce is too heavy for the motive force. — 
The watch being wound, move the balance exactly to its neutral 
or central position, (as it would stand if at rest, free from the 
motive force,) and liberate it. It should start going, of itself. 
If it does not, the balance is too heavy — provided the escape- 
ment is correct and in beat. Also notice how long it takes to 
acquire its full vibration. If it requires 12 or 15 vibrations to 
reach its full motion, the balance is probably too heavy, or the 
motive force is too weak ; and the reverse is the case if it 
gets into full vibration almost immediately. But only experi- 
ence can enable the workman to judge positively from such 
tests. The timing may also indicate when a balance is too 
heavy by the difficulty of timing in positions, i.e.., to get the 
same rate hanging and lying down. If the motive force is also 
too weak for the balance, it will gain while horizontal and lose 
while hanging up. See section (399). 

(424.) Oiling. — As the oil plays an important part in the per- 
formance of the cylinder escapement, its proper quality and 
application should be attended to. Oil which is too thin and 
fluid is not suitable, as has already been explained (416). An- 
other reason is that a very fluid oil has a tendency to spread and 
leave the rubbing surfaces. For example, it would leave the 
lip or shell of the cylinder to run on the teeth, and from the 
teeth it would run down the standards or stalks of the teeth and: 
foul in the slot and elsewhere. The American oils which are^ 
not too thin will be suitable for the pivots, but for the teeth and 
cylinder the imported Rodanet oil is preferable. All oils should 
be kept in bottles tightly corked, and in the dark, and should' 
be kept fresh in the oil box. 

(425.) Applying the oil. — After putting a minute drop of oil in 
the pivot holes of the cylinder, run a fine clean pegwood point 
into the hole, to carry the oil through to the end stone, — (other- 
wise it may remain at the surface, and the shoulder of the pivot 
coming in contact will draw it away and leave the inner part of 
the hole almost dry.) Having done so, then apply a little more 
oil to the hole. Apply a very little oil to the two lips of the 
cylinder where the teeth act upon them, rubbing the oiling wire 
up and down to moisten them. Then apply a little oil on the 
incline of each tooth. When the job is finished oil the escape- 
wheel pivots, moving the pivot with the oiling wire to be sure 
that it enters the hole, but not using enough for any to possibly 
run down into the pinion. 



l8o THE WATCH ADJUSTER'S MANUAL, 

CHAPTER XXVI. 
Duplex Watches. 

(426.) General characteristics. — The duplex, like the cylinder, 
is a frictional escapement and has what we have called " natural 
compensation," (393, 416, to 419.) It does not need either an 
isochronal hair spring nor compensation balance, and is usually 
better off without them. But it is very sensitive to variations 
in the motive force, and hence is not so well adapted for going- 
barrel watches as the cylinder escapement. In watches not 
provided with chain and fuzee, stop works should always be 
used on the barrel, and they should be so arranged as to secure 
as nearly uniform motive force from the mainspring as possible. 
The best results are obtained with a somewhat strong motive 
force — considerably stronger than would answer for the cylinder 
escapement. The duplex is also very sensitive to shaking and 
jarring, and is, therefore, unsuitable for very active persons, 
those who jump about, ride horseback, indulge in violent ath- 
letics or sports, and it is impossible to guarantee good perform- 
ance in such cases, — although duplex watches with very quick 
trains have sometimes performed well. But for persons of quiet 
or sedentary habits, or when not worn but left hanging in the 
house or lying on a table, etc., it is capable of running very 
closely. 

(427.) The hair-spring. — The duplex performs best with a 
rather short hair spring; about 10 coils is usually best. But in 
watches having very large vibrations, such as were formerly 
made, and are yet by the French and Swiss makers, a larger 
spring should be used — up to 12 coils, or even more in some 
cases. In the duplex, the hair spring is thought to perform best 
when pinned nearly half a turn short of complete turns. It 
should not be bent from the regular spiral form at the ends 
where pinned, but should be pinned without any bending at 
either the stud or the collet. The latter point is especially 
important. The coils should be regular in form and equidis- 
tant from each other, with uniform strength from one end to 
the other. 

(428.) The vibrations. — The duplex generally has 18,000 vi- 
brations per hour, and even more. It should not have less than 
18,000. When it has only 14,400 or up to 16,000 per hour, 
with a. heavy, balance, the motion is so slow and sluggish that 



THE WATCH ADJUSTER'S MANUAL. i8i 

the watch is very liable to trip or set. But if the proportion 
between the escapement, balance, and motive force is correct, 
it can hardly have too quick a vibration, even up to 24,000 per 
hour. The usual arc of vibration is 360°, or just i turn. But 
it is often made larger or smaller than that for special timing 
purposes. 

(429.) In beat. — When the parts are in their proper relative 
positions, and the balance is at rest, the notch in the ruby roller 
should be between the locking tooth resting upon it and the 
line of centers, (line from the center of the balance staff to the 
center of the escape wheel), or a very little nearer to the line of 
centers. Many workmen place the center of the notch on the 
line of centers, but the previous position is considered preferable, 
unless the motive force is very strong. In that case, the notch 
is so placed that the locking tooth is just on the point of drop- 
ping into the notch, i.e., the balance moves but little to let the 
tooth pass into the notch, and considerable to let it out. 

(430.) Sizes of parts. — The diameter of the ruby roller should 
be -g- the distance between the points of two locking or resting 
teeth, or y^g- the diameter of the escape wheel. The sizes 
throughout the escapement are taken with the escape wheel 
as the basis. The wheel and teeth must be very accurately 
cut, and the impulse (or upright) tooth must be midway be- 
tween two locking (long) teeth. The wheel must be as light as 
possible, and accurately poised. The length of the impulse 
pallet ox finger is governed by the number of teeth in the wheel 
and the angle of lift, or intersection of the impulse teeth and 
impulse pallet. No fixed proportion can be specified, but the 
object is to have the intersection deep enough for safety and 
wide enough to give sufficient lift or impulse. The points of 
the impulse teeth are generally at two-thirds the distance from 
the center to the points of the locking teeth. 

(431.) The drops. — When the locking tooth slips out of the 
notch in the roller, there is an e?igaging drop on to the impulse 
pallet; when the impulse tooth passes off the pallet there is an- 
other or disengaging drop, that of the locking tooth on to the 
ruby roller. The amounts of the drops are very important. 
The engaging drop is adjusted by turning the impulse pallet on 
the balance staff; moving the pallet towards the notch makes 
the engaging drop greater and vice versa, but moving it from the 
notch does not increase the disengaging drop: that is governed 
by the length of the impulse finger or pallet, and should be no 
greater than is necessary for freedom of action, as excessive 
drop on to the ruby roller is liable to spring the balance staff, 



i82 THE WA TCH ADJUSTER'S MANUAL. 

loosen or break the roller, etc. The disengaging drop is also 
varied by getting the balance staff and escape wheel closer or 
further apart. About io° of balance movement is usually 
allowed for the engaging drop, and a little less for the disengag- 
ing drop. 

(432.) Examining impulse and drops. — Bring the balance to 
rest with the locking tooth resting against the roller. See if it 
is in beat (429). Move the balance slowly back the [dumb 
vibration), to see if the end of the impulse finger safely clears 
the impulse tooth behind it, (the tooth which has just left the 
pallet) ; let the locking tooth fall into the notch, and see that 
there is no danger of its point escaping past the other lip of the 
notch when it falls, nor catch on the corner of the notch; try 
the freedom of the tooth in the notch in all positions as you 
move the balance slowly back; go on so till the locking tooth 
again rests on the outside of the ruby roller, and see if the 
point of the impulse finger clears the impulse tooth in front of 
it, trying it repeatedly, to be sure. If there is too much space 
between them when they pass, it may show that the intersection 
is too shallow for safety. 

(433,) The engaging drop. — Now move the balance forward, 
i.e., in the direction of its acting or i7npulse vibration, let the 
locking tooth again fall into the notch, and very slowly move 
the balance forward till the tooth slips out of the notch and the 
impulse tooth drops on to the finger, and hold the balance there; 
this is the engaging drop. This drop should be sufiicient, {i.e., 
the pallet should be far enough in advance of the tooth,) to en- 
able the point of the tooth to lap on the face of the impulse 
finger far enough to secure a safe action. If the tooth misses 
the pallet, or catches on its corner, the drop must be increased, 
(431,) or the finger lengthened, or the impulse pallet jewel (if 
there is one on the finger) must be moved outward; or in ex- 
treme cases, where only the drop can be increased and would 
then be too great for a good action, the balance staff and cen- 
ter wheel must be brought closer together. But generally (if 
the locking action is correct) a new impulse finger would be 
better. The intersection being safe, move the balance forward, 
see that the tooth acts on the pallet long enough to give a good 
impulse, and notice the amount of the drop when the tooth 
passes off the pallet, again trying the freedom of the pallet 
when passing the tooth which has just dropped. If the wheel 
is true, this examination will show the condition of the whole 
escapement. 

(434.) To test the safety of the impulse intersection. — When the 



THE WATCH ADJUSTER'S MANUAL. 183 

balance pivots are rather loose in their holes, the play may 
make considerable difference in the action in different positions, 
/.<?., whether the balance is nearest to the escape wheel or fur- 
ther from it, and a special test is then needed for the safety. 
With the watch wound a little, put a pegwood point inside of 
the balance rim and press it towards the wheel, pass the impulse 
finger by the tooth, back and forth, to see if they can touch, 
where they should clear. Do this with both teeth — the one 
which has just acted, and the one that is ready to act. 

(435.) Then put the pegwood on the outside of the balance 
rim, and press it from the wheel. Try if the impulse tooth 
drops safely on the pallet when the latter is advanced very 
slowly towards the waiting tooth. If it catches on the corner 
of the pallet, and that is considerably rounded, dressing the face 
down level to the edge may lengthen the finger sufficiently. 
(The face must be in line with the balance axis.) If it does 
not, the pallet should be turned on the staff to make the inter- 
section deeper when contact occurs, {i.e.^ turned toward the 
roller notch,) as directed in sections (433, 446). This must also 
be done if it is found that some of the teeth are shorter than 
others, and do not catch safely, while the others do. When the 
teeth are not even, both of these tests should be made with 
every tooth. 

(436.) Examining the escape wheel. — About the only way 
open to the jobber is to examine the action in the watch. Per- 
haps the best way to tell whether the locking and impulse teeth 
are uniform and at equal distances apart is to repeat so much of 
the foregoing test as necessary, with each tooth on the wheel. 
Let the impulse tooth drop off the pallet, and while the locking 
tooth rests on the ruby roller examine the clearance between 
the end of the impulse finger and the tooth which has just left 
the pallet. Hold the movement so you can see the light be- 
tween them as they pass, holding the balance still at that point. 
If the clearance is the same for all of the impulse teeth, the 
wheel may be considered true. 

(437.) To test the locking teeth., hold the movement so that the 
line of sight will be along the front of the tooth, and observe 
how near the edge of the roller the point of the tooth stands. 
Now let the watch run, observing the position of each tooth. 
If some are longer, they will stop nearer the edge, while the 
short teeth will be able to get nearer the center of the roller. 
As the tooth retains its position during the remainder of the 
acting vibration (after the disengaging drop) and during the 
first half of the return or dumb vibration, there is time enough 



i84 THE WA TCH ADJUSTER'S MANUAL. 

to observe closely. The wheel can be examined in the calipers, 
by setting the point of the slip or toucher very accurately, to 
see whether the wheel is out of center, i.e.^ if some of the teeth 
reach further from the center than others. 

(438.) Correcting the wheel. — Try both sets of teeth; the 
locking, and the upright or impulse teeth. If they are concen- 
tric at their points, but some of the locking teeth are bent and 
irregular, about the only way to get them uniform is to make a 
templet, one edge of which is so shaped as to rest against the 
pivot, and also along the front side of the teeth. If the templet 
rests against the root of the tooth, but not the point, the point 
has been bent back; if it hits the point, but not the root, the 
tooth is bent forward. The templet is, of course, fitted to a 
tooth which appears sound and correct. The impulse teeth can 
be tested in the same way. The width of the templet at the 
points of the teeth can be made equal to the proper distance 
between the points, and will show if the points are evenly 
spaced. 

(439.) Topping the locking teeth. — This can be done by insert- 
ing the wheel and pinion in a depthing tool, and adjusting an 
oil-stone slip against the centers of the other jaw, (the one 
nearest the adjusting screw,) so that it will nearly touch the 
longest tooth. While rotating the wheel with a very fine hair 
and weak bow, gently press the jaws of the tool together with 
the fingers. They will spring enough for the oil-stone to get 
the points all of equal length. Then smooth the corners with 
very fine burnisher. The straightening and evening of the teeth 
must have been previously done. 

(440.) General condition. — The balance staff should not have 
much end-shake, or the pivots will wear rapidly; in that case 
they should be repolished and new jewel holes fitted — at least 
to the bottom pivot. The balance pivots require to be well 
fitted. If the holes are too large, every change of position 
causes errors in the running, because it changes the frictions 
and the action of the escapement. The duplex does best with 
a strong motive force and rather heavy balance. When the 
balance has timing screws in its rim, it should be riveted on the 
staff in such position that these screws will be in a vertical line 
through the staff, when the balance is at rest and free, with the 
watch in the hanging position. This is to admit of adjusting 
for positions by altering the poise (422). 

(441.) Impulse pallet and teeth. — The acting face of the im- 
pulse pallet should be in a radial line to the balance center, and 
the front of the impulse tooth should be parallel with it when 



THE WATCH ADJUSTER' S MANUAL. 185 

they meet. Otherwise either the pallet or tooth will be cut and 
pitted by the corner striking it. In a fine watch intelligently 
made, the position in which the faces are parallel would evi- 
dently be where the maker intended the contact to occur, but 
in common watches the workman must arrange the drop where 
he thinks the action will be best. Some recommend that the 
pallet should be just ahead of the tooth when it drops, while 
others advise that it be placed considerably ahead of it, so that 
the tooth will have considerable drop before it reaches the pallet. 
Perhaps the best way is to arrange each case according to what 
it requires to give the best perfoimance. A very slight increase 
of drop on the impulse pallet considerably lessens the balance 
vibrations ; and vice versa. 

(442.) Lockifig teeth and ruby roller. — If the locking intersec- 
tion is shallow, there will be straining of the balance staff, by 
the tooth nearly passing by the roller, with engaging friction or 
wedging, springing the staff, danger of splitting the ruby roller 
— also danger of tripping, and of setting, if the watch is jarred 
or shaken while the tooth is on the roller. If the notch is wide, 
there is also danger of the tooth slipping by the corner and trip- 
ping; the recoil is also greater. The roller must be perfectly 
concentric with the balance staff. The notch should be no 
wider than necessary for freedom of the teeth, and the corners 
should be but little rounded, well polished and perfect. The 
notch should have sufficient depth to avoid any danger of the 
point of the tooth grazing the bottom. No rule can be given 
for the size of the ruby roller. The great point is to have the 
intersection safe. The custom of jobbers is to have an assort- 
ment of rollers, fit on one which seems likely to be suitable, 
and examine the action, with the balance and escape wheel 
in the depthing tool. If not good, take another size, till 
correct. 

(443.) Safety tests for positions. — The watch being wound, hold 
it edge up, with the balance below the wheel and falling away 
from it. Run it long enough to see if there is any sign of 
catching or irregularity. If so, the locking intersection may be 
too shallow, (433,) or the impulse finger and pallet may fail to 
meet properly, (441). Notice the extent of the vibrations, 
then reverse the positions and have the balance above the wheel, 
and falling towards it. If the vibrations fall off, the locking 
teeth may not be free in the notch, or the impulse teeth may 
catch on the point of the pallet as it passes them during the 
dumb vibration. This latter fault can be heard if the watch is 
in the case. If there are two locking teeth to each impulse 



i86 THE WA TCH ADJUSTER'S MANUAL. 

tooth, the roller must be perfectly free when between the double 
teeth, in this position. 

(444.) Ru7ining or overrunning. — If the balance vibrates too 
far, (during the impulse vibration,) two teeth will pass at a 
single vibration, causing the watch to gain. It is generally due 
to a mainspring too strong or balance too light. If the inter- 
section of the locking teeth on the ruby roller is shallow, the 
watch is liable to ru7ini?ig. If this fault is inveterate, it can be 
prevented by a banking pin in the balance and another in the 
plate below the balance, arranged to come in contact at the 
proper time and prevent the balance vibrating over one turn — 
precisely as in the case of the cylinder escapement (406). But 
nowadays this contrivance is seldom seen, the error being 
guarded against by more careful usage by the wearer. Besides, 
it is liable to cause rapping^ which is almost as bad as running, 

(445.) Setting may be due to a balance too heavy, too narrow 
a notch in the ruby roller, or one whose edges are rough or 
chipped, or the points of the locking teeth are damaged, too 
thick, or not vertical, so that they clog in the notch as if they 
were very thick. In a narrow notch, the thickening of the oil 
clogs the teeth and increases the liability to set. Setting is also 
more liable to occur if the engaging drop is too small and the 
impulse tooth has to impel the pallet too far before it can es- 
cape. Similarly, the watch is more liable to stop when it is out 
of beat, in such a way that the locking teeth have to move the 
roller around a great distance before they can escape from the 
notch. If this fault is inveterate, it may be well to place the 
roller notch on the line of centers. See In beat, (429). Then 
the balance will move an equal distance each side from the 
point of rest, in order that the locking tooth may enter the 
notch and leave it. A stronger mainspring is generally advisa- 
ble, unless the watch is also addicted to tripping or running, in 
which case the best plan would be to make it red-hot and then 
pulverize it. 

(446.) Isochronal adjustment. — If the escapement frictions re- 
main the same, and the arcs of vibration are made larger, (as by 
a greater motive force, or by a better action of the escapement, 
making the motive force more effective,) the long vibrations 
will be slower than the short ones, and vice versa. See section 
(570). Moving the impulse pallet towards the roller-notch in- 
creases the engaging drop and makes the vibrations smaller, and 
the long vibrations will be quicker than the short ones, but this 
should not be done when the angle between the impulse pallet 
and the notch is less than about 10°, as that amount is consid- 



THE WATCH ADJUSTER'S MANUAL. 187 

ered necessary. Moving the impulse pallet away from the 
notch and so increasing this angle, increases the arc of vibration 
and also makes the long vibrations slower than the short ones. 
But if moved too far, the impulse tooth will catch on the corner 
of the pallet, or even fail to hit it at all — the tooth getting past 
the pallet before the intersection becomes deep enough for con- 
tact to occur, (432, 433.) Another way to accomplish the same 
results is to put the watch out of beat. For instance, to make 
the short vibrations faster than the long ones, move the hair- 
spring collet on the balance staff so as to make the roller notch 
stand nearer to the tooth resting on it, when the balance is at 
rest. But this makes the watch more liable to set, and should 
not be done except when the motive force is very strong (429). 
The pinning of the hair spring can of course be varied to im- 
prove the isochronism, as with levers and chronometers. 

(447.) Natural coi7ipensation for positions. — When the watch is 
correctly designed and well made, the proportion between the 
motive force, the momentum of the balance, and the strength 
of the hair spring produces a "natural compensation" for differ- 
ent positions and for different arcs of vibration. But when this 
proportion does not exist, it is useless to expect to correct the 
errors by changing the hair spring, unless that is the part at fault, 
when it should of course be corrected. The effect of play or 
looseness in the balance pivot holes has already been mentioned 
(434). When the watch is in the position which allows the bal- 
ance to fall closer to the escape wheel, the long vibrations will 
be quicker than the short ones, and vice versa. If this action 
can be utilized it will help to perfect the " natural compensation 
for positions." That would be done by arranging the move- 
ment in the case so that when the watch was in the hanging 
position the balance would be over or under the wheel, accord- 
ing to the effect desired. 

(448.) To time the duplex in positions. — This is done by chang- 
ing the poise of the balance. The method of altering a plain 
balance or an ordinary screw balance, has already been de- 
scribed, and is the same as for the cylinder escapement. See 
sections (421, 422.) When the balance has timing screws, (440,) 
and has been riveted on the staff so that they are in the vertical 
diameter when the balance is at rest, hanging, and the roller 
notch is in the correct position relatively to the rest of the es- 
capement, the poise of the balance can be changed by moving 
the timing screws in or out as required. If the ruby roller was 
set after the balance was riveted on the staff, it should be 
cemented on in the proper position relatively to the timing 



iSS THE WATCH ADJUSTER'S MANUAL. 

screws, which is easily done by marking the direction of the line 
of centers on the rim. If the balance is too heavy, it will be 
more difficult to time in positions. And if the vibrations are 
more than one turn in extent, this method is not suitable, for 
the effect will be one way with the small arcs, and just the re- 
verse with long arcs. 

(449.) To test if the halaiice is too heavy for the motive force, 
(the escapement being in proper condition,) slowly move it back- 
ward till the locking tooth enters the roller notch, then liberate 
the balance; and it should start to going without assistance. 
If it does not, the balance is probably too heavy, or the watch 
is not in beat, (429, 445). 

Another way is to see how long a time is required to attain 
its natural vibration, as directed for the cylinder escapement 

(423)- 

(450.) Oiling the duplex. — Put oil to the pivots, and a little in 

the notch of the ruby roller, but none on the impulse pallet or 

teeth. 



CHAPTER XXVII. 

Lever Watches. 

(451.) General characteristics. — The lever is often called a de- 
tached escapement, but in reality it is only semi-detached. The 
action is more or less affected by every detail of construction 
throughout the entire escapement, and a dozen different faults 
may convert it into a worse than frictional escapement — for the 
friction in the latter may serve a useful purpose, in controlling 
and regulating the balance, while in the lever it would be purely 
detrimental. For an example, take the rubbing of the safety 
pin on the roller; its effect is entirely harmful, with the single 
exception that it prevents the occurrence of something even 
worse than itself. Nevertheless, when well made and adjusted, 
it is the best escapement in use for pocket watches, and even 
the low grades have no rival for serviceability in common or 
rough usage, except the cylinder escapements. Its performance 
will be in proportion to the conformity of its parts to the correct 
standard, more than to the fineness of its finish. It is useless to 
attempt to closely time or to adjust a movement which is not in 
good condition. The timing being directly affected by the es- 
capement, and being varied by changing the latter in different 
ways, many details regarding the mechanical proportions and 



THE WATCH ADJUSTER'S MANUAL. 189 

arrangement of the various parts are necessarily given. It is 
believed that they will pretty fully cover all contingencies, and 
enable the workman to detect the cause of any fault he meets 
and know the proper remedy. For good performance the lever 
requires both an isochronal hair spring and a compensated bal- 
ance; and after the special directions in this chapter have been 
carried out, the "adjustments" may be applied and perfected as 
hereinafter given, with confidence that the performance of the 
watch will be worthy of the time and labor expended upon it. 

(452.) Technical names. — The escape wheel may have ratchet^ 
pointed or star teeth^ or club teeth. The outer surfaces of the 
latter are i7npulse planes^ the sides are called the locking and the 
heel. 

On the pivoted lever staff qi arbor, sometimes called the pallet 
arbor or staff, are the pallets and the long part called the lever 
fork, or lever. The ends of the pallets are arms; the one the 
tooth strikes first is the entering arm, the other is the exit arm. 
The belly of the pallets is between the arms. Each arm has a 
pallet jewel ox pallet stone for the teeth to act upon. The front 
surfaces are the ifnp ids e planes or inclines; the sides are the lock- 
ing or locking face, and the exit or discharging face. The horji of 
the lever is the curved part on each side of the notch in its end, 
just behind the notch is th^ guard point, or pin, or the safety pin; 
in the double roller escapement, the safety pin or guard finger 
projects forward, under the notch. 

On the balance staff is the table roller, carrying the ruby pin 
or impulse pin; in the edge of the roller, in front of the pin, is 
the passing hollow or crescent. The double roller escapement 
has two rollers; the table roller or impulse roller which carries 
the ruby pin, and a smaller or safety roller has the crescent in 
front, and its edge keeps the safety pin from getting by the 
roller when the lever is pressed backward. 

(453.) The hair spring. — Springs with 14 coils are thought to 
be best, but some prefer 12. When the springs are unhardened 
and soft, as in cheap watches, a longer spring is necessary, in 
order to avoid bending by use. But this only preserves them 
for a time, and in a few years they frequently require re-spring- 
ing in order to do even decent service. The above refers to 
the flat spiral springs — the only form, except the Breguet, that 
is used in lever watches. If the flat spiral does not vibrate over 
\\ turns, it can be isochronized very closely. If the vibrations 
exceed i\ turns, the Breguet form should be used, and abroad, 
20 coils are considered best. (The American watch factories use 
14 to 15. See Chapter VIII.) For small watches, a turn or 



IQO THE WATCH ADJUSTER'S MANUAL. 

two less will be better, as 12 or 13 coils for the flat spiral, and 18 
for the Breguet. If the work is cheap and poor, either 
watches of ordinary size or smaller ones with quick trains 
should have shorter springs, in order to get the short vibrations 
fast enough. The diameter of the hair-spring collet should be 
rather small, the spring should be evenly coiled, of even hard- 
ness and temper from end to end, and the inner end should 
meet the collet without departing from the spiral form. With 
the ordinary flat spiral, the outer end should meet the stud in 
the same way. Both the flat spiral and the Breguet are pinned 
in even turns. 

(454.) The vibratio7is of a lever watch are generally 18,000 
per hour, but some English levers are made with 16,200 vibra- 
tions per hour. But watches will occasionally be met having 
all the way from 14,400 up to 21,000 beats per hour. 

(455.) In beat. — The lever is in beat when the center of the 
ruby pin is on the line of centers, i.e..^ a straight line between 
the center of the balance and lever staffs. The center of the 
lever notch, of the safety pin or guard point, and of the crescent 
should also be on that line, and in the double roller escape- 
ment, the center of the guard finger must likewise be on the 
line of centers. When the escape wheel is pressed slowly for- 
ward, the balance should be moved an equal distance each way 
from the central position (or point of rest, when the balance is 
at rest and controlled only by the hair spring,) in order to es- 
cape, and the lever should be securely fixed to the pallets in 
such position that it will move the balance as described. 

(456.) The balance. — The diameter of the balance is generally 
twice that of the escape wheel. But when the wheel is smaller 
than usual and the motive force is strong, it may be 2\ times 
as large. This is a good rule for English levers. Another rule 
is that, in a full plate watch, the diameter of the balance should 
be half that of the top plate, and, in a three-quarter plate watch, 
it should be the size of the inside of the barrel for a 16, 200 train, 
and a trifle smaller for an 18,000 train. It is supposed that this 
will insure the size of the balance being suitable for the strength 
of the motive force, but it is obviously but a rough rule, al- 
though sufficient for the needs of the jobber. The manufacturer 
would need to make a far different calculation if he expected 
his products to do him any credit. The balance should be tolera- 
bly heavy — considerably heavier than for the cylinder escape- 
ment — in order to perform the unlocking without affecting its 
motion. A light balance is greatly affected by variations in the 
motive force and by imperfections of any kind in the escape- 



THE WATCH ADJUSTER'S MANUAL. 191 

ment; there being but little friction at the pivots, there will be 
but little variation between hanging up and lying down. The 
heavy balance, having greater friction at the pivots, will vary 
more in the different positions, besides being more liable to in- 
jury by falls, etc. For plain balances, gold or brass is pref- 
erable to steel. 

(457.) Oiling. — The lever is much affected by the oil used on 
the escapement, and none but the best quality should be em- 
ployed. It requires cleaning at least every eighteen months, 
and cleaning yearly would greatly improve its performance. 
On the pivots of the balance staff, pallet staff and escape wheel 
thin and very fluid oil may be used, but care must be taken not 
to apply too much, as it is likely to run off and leave the pivots 
running dry. Avery little oil is also applied to the faces of the 
pallet jewels. After the wheel has gone around two or three 
times, apply a very little more, let the wheel go a few times 
around till each tooth has got its point oiled, then with a peg- 
wood point absorb the oil from the pallet faces, and what re- 
mains on the teeth will oil them sufficiently. When the pallets 
are not accessible, oil the teeth only, as described. For the 
other pivots and bearings an oil with more body should be used. 
No oil is applied to the escapement except as above directed — 
none on the ruby pin, guard pin, none in the notch of the lever, 
or in the crescent, or on the roller. The escapement should 
not be oiled till the watch goes together for the last time. 

(458.) General examination. — There are a hundred possible 
faults, any one of which may affect the running, render it im- 
practicable to secure a close rate or adjustment, or may even 
cause stoppage. Some of those we shall mention may seem too 
trivial to dwell upon, but, trivial though they be, they are im- 
portant enough to spoil your work and damage your reputation. 
They must be attended to, and therefore we shall specify them, 
and you will do well not to overlook any of them. Of course, 
only a few out of the number, or perhaps a single one, will be 
found in any one watch, but that one may be the very thing that 
ails your watch. Only faults which are liable to occur in the 
lever watch are here mentioned. For those which might be 
found in any of the other escapements, see the other chapters 
of Part Fifth. 

(459.) The pivots., staffs^ etc. — The balance pivots in the lever 
do not need to be so closely fitted as in the duplex, but more so 
than in the cylinder. They, as well as those of the lever staff, 
should be well fitted in their holes, (those of the lever being 
closest,) but not too closely, as then the thickening of the oil 



192 THE WATCH ADJUSTER'S MANUAL. 

would be too much felt. But if the pivots are too loose, there 
will be more variation in the different positions. Still, it is bet- 
ter to have them a little too free than too close. If the balance 
and other cocks do not come off easily, from the steady pins 
sticking or otherwise, you should always look out for bejit 
pivots^ especially on the lever and balance staffs. The pivots 
should always be perfectly straight, round, and of equal size 
(not tapering) as far as they go in the holes, polished or bur- 
nished, with end-shake ample for freedom but no more, and the 
end-shakes should be equal for the balance and lever staffs and 
the escape wheel. All of them should be perfectly vertical and 
parallel to each other. In a good watch, the balance pivots 
should both be of the same size. 

(460.) The jewels^ pins, bankings, rollers, etc. — Examine care- 
fully to see if the pallet jewels, the ruby pin and the hole jewels 
are tight in their places. For the end stones, see sections (17 to 
19). See that the guard pin or finger, and the banking and 
regulator pins are tight, vertical, clean, smooth and dry. See 
that the roller table and the hair-spring collet are fast on the 
staff, the ruby pin vertical and parallel with the staff, and that 
the lever is rigidly fastened to the pallets and moves precisely 
as they do. Be sure that the ruby pin cannot get on top of 
the horn of the lever. When the lever banks against the sides 
of the sink, see that they are vertical and free from oil, etc., 
and that they have only a narrow edge in contact with the lever. 
Take the same precautions if the lever banks against a pinion 
arbor or elsewhere. See that the end of the ruby pin does not 
graze against the bottom of the sink it revolves in, nor on the 
point of the screw which holds the bottom end stone, nor on 
any burr around the screw-hole, nor fuzzy fibres sticking in any 
hole or corner or held by oil or grease in the sink. In the 
double roller escapement, raise the lever to the highest position 
its end-shake will allow, while the ruby pin stands over the guard 
finger, (in its lowest position,) and see if they come danger- 
ously close. If so, set the ruby pin higher or the guard finger 
lower till they clear. See that the safety pin cannot get above 
or below the safety roller. The ruby pin should not be round, 
as that form gives a poor action in the lever notch unless the 
depthing is exact. The oval form is better, or a round pin with 
the front third ground off flat, or a triangular pin, with a flat 
side outward. Exactness in the points mentioned in this and 
the preceding section will greatly facilitate the timing in posi- 
tions. 

(461.) The lever. — The notch should be square to the bottom 



THE WA TCH ADJUSTER'S MANUAL. 193 

— not tapering, and wider at the outside; the sides should be 
straight, smooth and polished; the ruby pin should have no 
play, but only be fully free; the notch deep enough to prevent 
the pin from bottoming, or from fouling or clogging if a little 
oil, fuzz, or dirt gets in; its outer corners but slightly rounded 
off, enough to remove sharpness, and polished ; and the inside 
of the horn should be formed to correspond to the path of the 
ruby pin while the guard pin rests against the edge of the roller — 
allowing space enough for the ruby pin to clear it safely while 
passing towards the notch. In the single or table roller escape- 
ment, the lever notch and the crescent are so made that the 
guard pin enters its crescent at the same time that the ruby pin 
enters the lever notch, and without touching the corner of the 
crescent in passing. The slightest grazing in passing would 
seriously affect the vibrations and timing. In the double-roller, 
the guard pin passes into its crescent some time before the ruby 
pin enters the lever notch, but the horn must be wide enough 
for the ruby pin to be within the horn before the guard pin 
passes into the crescent. The lever (with pallets and every- 
thing complete on the staff) should be accurately poised, and 
in an adjusted watch the escape wheel should also be poised. 
It should be unnecessary to say that regarding the balance, etc. 
(462.) The wheel and pallets. — To go fully into the wheel and 
pallet action would be equivalent to a treatise on the lever es- 
capement, which is hardly within the purpose of this book. I 
shall suppose that the workman understands how it should be, 
and will only give a few points, as reminders of faults to be 
looked for. The wheel must of course be true in the flat, and 
the teeth true in the round, {i.e.^ concentric with the axis of the 
pinion,) all alike or equal, straight and in good condition. The 
wheel and pallet should be set as closely together as possible. See 
that the teeth clear the belly of the pallets, and cannot rub up 
under the lever, nor foul with oil or dirt on either of them. 
Examine the freedom of the teeth. If the lockings are too 
shallow, and plenty of shake inside, the wheel is too small; if 
the lockings are too deep, with great freedom or shake outside, 
the wheel is too large, and may be corrected by topping. (See 
439.) Supposing the wheel and pallet action to have been ex- 
amined, (including the locking, the draw, the impulse, the drops 
and the freedom,) wind the watch partly up and listen to the 
tick. If irregular, there may be some teeth thicker or longer 
than others, or bent. Any grating is also to be looked into. 
If the tick is regular and clear, we will next examine the most 
important point, viz. : — 

13 



194 THE WATCH ADJUSTER' S MANUAL. 

(463.) The roller action. — Fold a narrow slip of tissue paper 
once, and place under the balance rim, so that, in trying to 
open, it will hold the balance still in any position, but will not 
have force enough to spring or strain anything. Put the bal- 
ance in the central position and test (both by feeling and by 
examining with the magnifying glass,) if the ruby pin is free in 
the lever notch but without too much play, and the safety pin 
or guard point is free in its crescent. Move the balance slowly 
around, constantly testing to see that the safety pin remains 
free in the crescent and the ruby pin free in the notch till it 
passes out of the notch and the tooth drops off one pallet and 
onto the other. Try this in both directions from the central 
point. 

(464.) The locking action. — When the tooth drops, as just 
stated, it should drop onto the locking face, not on the impulse 
plane. The latter would show a shallow pallet depth, and the 
watch cannot be timed if the tooth drops on the incline or just 
on the corner. When the locking is very shallow, try it with 
each tooth. If the teeth are irregular, the fault is in the wheel, 
which should be replaced. The corners of the pallets may be 
rounded, or chipped off, causing the tooth to drop on the incline 
when the locking is really deep enough. If the tooth drops too 
far up the locking plane, the safety or the banking action may 
be wrong. 

(465.) The draw. — Move the balance still further, till the 
ruby pin is free from the notch, and see if the tooth draws the 
lever against the banking pin; if not, jar the movement a little, 
and it should do so. If it does not, the locking face needs to 
be more inclined, to give it more draw. The watch should 
have ample draw, in order to keep the lever against the bank- 
ings, and prevent the safety pin from being thrown in contact 
with the roller while running, and so affecting the rate. 

Another test for the draw is the reverse of the above. Put 
the lever against the banking pin and jar the movement to see 
if the tooth will slide down the locking face and carry the safety 
pin against the roller. If the lever is poised, that would show 
that there not only was no draw to that locking face, but that 
it was inclined the wrong way. Another good test is, while the 
watch is running, to hold it so that you can see whether the 
lever strikes the banking pin and stays there, or stops short of it, 
and watch it awhile. Try this on both banking pins. If it 
occasionally fails to stand against the banking pin, the teeth 
are irregular, or depthing too shallow, or locking face has too 
little draw, or possibly the corner of the locking face may be 



THE WATCH ADJUSTER'S MANUAL. 195 

chipped or rough, and catch on the teeth. In the last case, the 
oil will rapidly become thick, with the powder ground off the 
teeth. If so, polish both the locking and the teeth. 

(466.) Freedo??i of the ruby pi?i. — Put the paper under the 
lever, move the balance slowly from the central position, and 
see that the ruby pin has an equal freedom from the inside (the 
hollow edge) of the horn of the lever, all the way out. In 
coming back, keep the safety pin against the edge of the roller, 
and see if the ruby pin is still free from the horn and if it can 
enter the notch without hitting the corner. If the safety pin 
cannot rest against the roller while the ruby pin is passing the 
horn, the ruby pin touches the horn, which should be altered to 
give clearance (461), or possibly the safety roller is too small, 
which is a serious fault and must be corrected. See section 
(469.) Where it is impossible to see whether the ruby pin grazes 
the inner edge of the horn, put a very thin coat of rouge (or 
whiting) in oil on iht fro7it, only, of the ruby pin, then move it 
from the central line outward, or the reverse way, with the 
safety pin against the roller. Do this on both sides. If the 
ruby pin touches the horn, (or the bottom of the notch,) rouge 
will be found there. Be sure to clean the rouge and oil off 
thoroughly, before going further. The space between the ruby 
pin and the edge of the horn should be more than the play of 
the safety pin between the roller and the banking. Of course, 
if the ruby pin (while being of proper shape) is too close to the 
inside of the horn and bottoms in the notch, that would indicate 
that it is set too far out, and should be moved further back in 
the roller. 

(467.) The unlocking action. — When the ruby pin enters the 
notch and passes to the further or unlocking side of it, to begin 
the unlocking, it must not hit on the (unlocking) corner of the 
notch, but safely on the inside of it. If its widest part hits 
barely on the corner, it must be set further out in the roller, or 
put in a pin of such shape that the contact point will be further 
from the roller center, so as to get a safe contact inside of the 
notch. When any change is made, repeat the above test, from 
each side, to the central point, till you are sure that the unlock- 
ing is properly accomplished in the notch. The locking (464) 
and the draw (465) have already been considered. 

(468.) The iffipulse action. — Remove the paper from under the 
lever, and put it under the balance, which is placed at its central 
position, with the mainspring partly wound, and the lever 
notch pressing against the ruby pin. Move the balance for- 
ward till the tooth drops, and the lever goes to the banking pin, 



196 THE WATCH ADJUSTER'S MANUAL. 

then slowly move the balance back till the tooth is unlocked 
and the lever flies forward with the other side of the notch 
against the ruby pin, urging it forward ; hold the balance still, 
exactly in the unlocking position, and see if the first contact is 
well inside of the horn. If the corner of the horn strikes below 
(i.e.^ further from the balance staff) the widest part of the ruby 
pin, a good motion or action is impossible. The necessity of 
square corners to the notch will now be evident. They should 
not be rounded off, but be polished barely smooth, i.e., not 
sharp. Get the first contact correct, and the correctness of the 
rest of it is already secured. Move the balance forward till the 
tooth drops, then still further, while noticing whether (i) the 
notch continues to press the ruby pin forward till the lever 
reaches the banking, and the ruby pin passes out of the notch 
without hitting the horn, or (2) the lever stops when the drop 
occurs, and the ruby pin has to carry it forward a ways in order 
to leave the notch — perhaps rubbing over the inside of the horn 
ail the way out. The former is correct, but the latter shows a 
lack of draw or poor locking. 

(469.) The safety action. — Remove the paper, and move the 
balance around till the tooth escapes and the lever goes to the 
banking. The safety pin should then be safely free from the 
roller edge. If not, the roller is probably too large, and should 
be freed by polishing off the edge. But if the safety pin has 
too much play, (between the banking pin and the roller edge), 
the roller may be too small, the safety pin too short, or not set 
near enough to the roller. While the lever is against the bank- 
ing, press the safety pin against the edge of the roller, and the 
tooth should still remain on the locking face of the pallet, when 
tried with both pallets. If not, it must be made to do so, either 
by lengthening the safety pin or bringing it nearer to the roller, 
or by a larger roller, and then, if necessary to give the safety 
pin freedom, the bankings must be opened. When pressing the 
lever back, as described, if the safety pin wedges against the 
edge of the roller, and seems almost likely to pass by to the 
other side, the safety pin (or point of the lever) must be set 
forward as above directed. In a double roller escapement the 
fault would be cured by a smaller safety roller and a longer 
safety finger. 

(470.) The banking action. — The primary object of the bank- 
ing pins is to give the teeth the proper amount of lap or run on 
the locking faces of the pallets, and no more. If the bankings 
are too close, the locking may be too shallow, and the whole 
action of the escapement confined within such narrow limits 



THE WATCH ADJUSTER'S MANUAL. 197 

that the slightest error anywhere or change of conditions will 
cause stoppage or derange the timing. If they are too wide, 
the unlocking is made more difficult and the entrance of the 
ruby pin in the notch more uncertain and imperfect, and the 
ruby may even pass by the notch and strike the inside of the 
horn, in which case good time is of course impossible. Any- 
thing that affects the proportion between the effective impulse 
given by the motive force, and the momentum of the balance, 
affects the rate, — and deeper lockings w^ill evidently have that 
effect. In fine watches, very little lap is required, and less is 
needed in the double-roller than in the single or table-roller 
escapement. But in coarse work, where the teeth maybe irreg- 
ular, the locking faces not properly inclined, the impulse planes 
too steep or too flat, etc., more lap may be required for safety. 
Of two evils, too much lap is better than too little, and in all 
cases there must be enough to make the action of the escape- 
ment safe — or else the escapement must be put in better condi- 
tion. The proper amount can only be told by trial. 

(471.) Changi?ig the bankings. — If the bankings are pins, they 
must not be bent inward or outward to alter the width between 
them, as that throws their contact sides out of vertical, and the 
lever would have different amounts of freedom when in different 
portions of its end-shake. It is an invariable rule that the con- 
tact surfaces must be straight, vertical and parallel with each 
Other. To open the banking, file away the inside of the pin, 
being sure to remove any feather-edges and filings, and leave it 
smooth, clean and vertical. To close the banking or lessen the 
play of the lever, pull out the pin, broach out the hole, and 
insert a larger pin, which will stand closer to the lever. An- 
other way is to file away the edge of the lever to give it more 
play; and another is to insert pins in a new place, at the proper 
distance apart, to lessen the play. In the former case, the 
lever must be poised again. As a general rule, the banking 
pins should allow equal play on each side, but as safety is the 
final test of correctness, they should be changed as required to 
secure that condition, remembering that the wheel and pallet 
action is the starting-point to be considered in arranging the 
bankings, and that in a fine watch the other actions should be 
made to conform to that, rather than open the bankings any 
wider. 

(472.) Setting. — If the watch setsor stops, (when clean, partly 
wound and in beat,) it may be due to any one among the fol- 
lowing causes: — 

I. If it sets with the teeth on the locking face of the pallet, 



198 THE WATCH ADJUSTER' S MANUAL. 

the locking is too deep; or the locking face is too much under- 
cut and has too much draw, /.<?., the locking is too strong. 
Small watches with light balances are most liable to this fault. 

2. If it stops or sets with the tooth on the impulse plane of 
the pallet, the impulse angle may be too great, />. , the incline 
is too steep; or the motive force too weak. I do not give 
directions for altering the pallets, as to do so properly would 
require many pages, and belongs more to watch repairing than 
to the adjustments. The work requires much study and expe- 
rience to understand just what to do and how to do it, and such 
alterations should be cautiously undertaken. 

3. If the teeth set part way up the impulse plane of one 
pallet, and not on the other, only the former is too steep. 

4. If the teeth set on only one locking face, that alone is too 
deep or has too much draw. 

5. The locking may be too shallow, and the teeth can drop 
on the impulse planes instead of on the locking faces; the bank- 
ing pin may be bent. 

6. There may be too little draw, or none at all, and shaking 
or jarring may jar the lever from the banking pins against the 
roller. 

7. The motive force too weak for the movement, or weak- 
ened by poor depthings or other faults, in the train. The lever 
escapement requires a rather strong motive force for good per- 
formance. 

8. Lever and pallets not poised, and jarring or change of 
position displaces them. 

9. The lever does not move with the pallets, not being firmly 
fastened to them, or on the pallet staff. 

10. Pallet jewel loose in the pallet. 

11. The lever too slender and springy, allowing irregular 
wheel and pallet action; or too short, so that setting backward 
or jars (see number 6) cause rubbing or overbanking. 

12. Watch gets out of beat, by loose collet, loose roller, 
lever loose on pallets, hair spring forced out of place by regu- 
lator, or jumps into or out of regulator, etc., — putting too much 
lift on one pallet. 

13. Ruby pin too loosely fitted in notch, or too closely; not 
set vertical; loose, and wedges or clogs in notch, or on corner; 
rubs inside of horn, or strikes inside or outside corner in pass- 
ing; ruby pin or notch rough; ruby pin grazes bottom of notch, 
or of sink; or grazes guard finger of double roller; ruby pin too 
short (or too much end-shake) and gets nearly on top of lever 
horn, or quite so. 



THE WATCH ADJUSTER'S MANUAL. 199 

14. Safety pin too short or table roller too small ; although 
not enough so to cause overbanking, yet the friction of the 
safety pin on the roller checks the motion and causes setting. 

15. Safety pin or guard point (or guard finger in double roller) 
not over the centre of the lever notch, and too close to the 
roller on one side, while showing the preceding fault when on 
the other side; pin accidentally bent. 

16. Safety pin hits corner of crescent in entering or leaving 
it, due to lever notch being too wide for ruby pin, giving it and 
safety pin too much play. 

17. The crescent in edge of roller too wide, so that the safety 
pin enters it too soon (before the ruby pin enters lever notch) 
and allows inside of lever horn to fall against the ruby pin. 

18. Crescent too narrow, or too shallow; safety pin hits on 
corner or bottom of crescent in passing. 

19. Escape-wheel teeth rub on belly of pallets, or up under 
lever, or oil gets between them and clogs the teeth. 

20. Oil between the lever and the banking pins, or sides of 
sink against which it banks, or dirt filling up banking space. 

21. Oil on safety pin and the roller, clogging or sticking them 
together; in a double-roller, oil between the ruby pin and guard 
finger. 

22. Oil in the lever notch, or between the under side of table 
roller and the lever horn, or between lever and under side of 
balance. 

23. Lever or other part magnetized, or in the vicinity of a 
magnet. 

(See Chapter III.) The foregoing are only a few of the 
faults which might cause setting, or so interfere with the action 
of the escapement as to prevent any close timing. If timing is 
difficult, look for every possible fault. (See Chapters II and 
XXXVII.) When the movement is in correct condition the 
various adjustments can be perfected by the methods given in 
Chapters XXIX to XLI. 



CHAPTER XXVIII. 
Box AND Pocket Chronometers. 

(473-) General characteristics. — The chronometer is a really de- 
tached escapement. If its parts are well made and arranged, the 
balance meets with only a trifling resistance in unlocking, the 
impulse is given in an almost perfect manner, and during the 



200 THE WATCH ADJUSTER'S MANUAL. 

remainder of the vibration it is entirely detached and free, while 
the whole of the return vibration is entirely free, except for the 
passing of the gold spring, which is so easily done as to be 
practically unnoticeable. The balance is therefore under the 
control of the balance spring only, (except during a minute por- 
tion of one vibration,) there being practically no other regulat- 
ing influence acting upon it. 

(474.) An isochronal hair spring and compensated balance 
are therefore absolutely indispensable for this escapement to 
give even fair performance, and the adjustment for positions is 
as necessary and useful for the pocket chronometer as for the 
other escapements. Under favorable conditions it is capable of 
giving the best performance of any portable time-keeper known. 
For marine chronometers, for example, where there is plenty of 
room for all the parts, ample motive force, of practically uni- 
form strength, and they can be kept in one position, it is 
almost perfect. 

(475.) But it is not adapted for pocket watches, except when 
carried by men who understand how it should be handled and 
are very careful to use it properly. For the use of ordinary 
wearers it is not so suitable as the lever. It also requires the 
very best workmanship in its construction and adjustment. 
While a very ordinary lever may give fair performance, a 
chronometer of the same grade might not be worth carrying. 
As only first-class workmen can do first-class work, the chronom- 
eter is more expensive than any other, both in its construction 
and repair, yet it is well known that the lever can keep equally 
accurate time, and is far more reliable. Its use in pocket 
watches is rapidly declining, and it is only a matter of time 
when it will be confined exclusively to box chronometers and 
semi-portable instruments of precision. 

(476.) The specific objections to its use in pocket watches 
are, that it is liable to "set," or stop, when exposed to jarring, 
shaking, jerks or twisting, which lessen the balance vibration; 
and if they increase the vibration, the watch will trip or over- 
run ; while a knock or shake at a certain time may displace the 
detent and cause mislocking, tripping or butting. Its heavy 
balance also exposes it to breakage of pivots. When taken 
apart for cleaning or repairs, it is not so certain to resume its 
former performance as the lever, but requires to be newly ad- 
justed and perfected, occupying a long time, and being trouble- 
some and unsatisfactory to the owner, as well as the workman. 
It cannot start of itself, but requires to be shaken. 

(477.) Nutnber of vibrations. — Marine chronometers have 14,- 



THE WATCH ADJUSTER'S MANUAL. 201 

400 vibrations per hour, or 4 vibrations per second. As the vi- 
bration in one direction is dumb, there is one beat to 2 vibra- 
tions, and they beat half-seconds. Pocket chronometers gener- 
ally have 18,000 beats, and some as high as 21,000 — the quicker 
trains being less liable to set, and less affected by shaking and 
carrying. 

(478.) Arc of vibi-ation. — The balance was formerly made to 
vibrate 360°, or one turn, but the present custom is to give it a 
vibration of 430°, or i^ turns, for both marine and pocket 
chronometers, as being less liable to set, and less sensitive to 
errors in the poise in different positions. 

(479.) The balance spring. — The cylindrical or helical form is 
used for both pocket and marine chronometers. The diameter 
of the coils is one-half the diameter of the balance, or \ inch 
in an ordinary 2-day chronometer, and a little under f inch 
from top to bottom. For marine chronometers, 11 to 13 coils 
are used, the highest number being preferred, and the ends are 
pinned \ turn short of even turns — springs so pinned being 
most nearly isochronal and regular in their action. For pocket 
chronometers, 7 to 10 turns, preferably the last number, are 
employed, and pinned in even turns. In the occasional in- 
stances when Breguet springs are used, they have about 20 
turns, and are pinned in even turns. 

(480.) Oiling the escapeinent. — Put no oil on any part of the es- 
capement — only on the pivots of the balance, the escape wheel, 
and the pivoted detent. 

(481.) E?td-shakes. — The end-shake of the balance staff and 
escape wheel should be ample for freedom, but no more, so that 
the parts cannot materially change their relative positions. 
The pivots should also be sufficiently free in their holes to 
avoid any risk of the slightest binding or clogging in any posi- 
tion, but not loose. When the balance pivots fit too closely, 
the thickening of the oil affects the vibrations very sensibly. 
The pivots of a pivoted detent must also be fitted as directed 
for the balance staff. 

(482.) The chronometer escapement. — As many workmen are not 
familiar with the construction and operation of this escapement, 
I have inserted Fig. 26, a diagram of the spring-detent form. 
The detent is supported by a foot b firmly screwed to the plate, 
and is carried at the end of the spring part g. At its other end 
is the pipe containing the locking pallet //, and an extension 
n^ called the nose or point, against which rests the gold spring 
s, screwed to the detent at w, and shown as just ready to drop 
off the unlocking pallet up^ held in the unlocking roller ^^r. As 



202 THE WATCH ADJUSTER' S MANUAL. 



O 




THE SPRING-DETENT 
CHRONOMETER ESCAPEMENT. 




THE WATCH ADJUSTER' S MANUAL. 203 

these last parts are underneath the impulse roller ?V, they are 
shown in dotted lines. The escape wheel ew\'=> shown as locked, 
by tooth J resting on the locking stone //. The tooth 2 has just 
dropped off the impulse pallet //, and tooth i is ready to drop 
upon the pallet as soon as the wheel is unlocked by tcp mov- 
ing the locking stone up out of reach of tooth j. c is the front, 
and c' the back, of the crescent or passing hollow in the impulse 
roller. The general principle of the bascule or pivoted detent 
form is the same, but the detent is carried by a pivoted staff at 
about i-, and the nose n is kept drawn towards the escape wheel 
by a small hair spring on the staff. The banking screw against 
which the pipe rests, and which is adjusted to vary the depth 
of the locking on the pallet //, would come under tooth j, and 
therefore it has been omitted for the sake of clearness. 

(483.) Technical terms and description. — The large form is 
called marine^ or box^ or ship' s chronometer ; the small form is 
termed pocket chronometer. The escapement is generally called 
detent^ or spring -dete fit ^ or chronometer escapement. When the^ 
detent and spring form one piece, as shown in Fig. 26, it is 
termed the spiHng-detent escapement; when the detent is carried 
upon a pivoted axis, it is known as pivoted-detent or bascule 
escapement. 

(484.) The escape- wheel tooth gives an impulse to the balance 
by impelling the impulse pallet u p.^ held in the ijjipulse roller u r 
on the balance staff, having its face or acting surface in line 
with the centre of the staff. The edge of the roller is hollowed 
out in a crescent c c' to free the escape-wheel tooth while giving 
the impulse, and the pallet projects into this hollow, about two- 
thirds of which, c, is in front of the pallet face. After the driv- 
ing tooth has given the impulse and passed off the pallet, it 
drops a short distance, when the wheel is stopped or locked hy a 
tooth resting on the detaining or locking pallet I p^ also called lock- 
ing stone., or simply locking. This is held in an opening or pipe 
in the detent^ which may be either a spring, s., or a pivoted 
detent. In the former case it is held against the banking screiv 
by its own elasticity ; in the latter, by a spiral recoveriftg spring 
around the detent axis, similar to a balance spring, but smaller. 

(485.) The balance having reached the end of its excursion or 
vibration, swings back again through the retia-n or dumb inbration., 
so called because it gives no beat while moving in this direction; 
nor does it receive any impulse. It would be entirely free if it 
did not hit the discharging or gold spring., g, with the discharging 
or unlocking pallet u p., held in the discharging roller., u r, on the 
balance staff. This spring is long and thin, and readily yields 



204 THE WATCH ADJUSTER'S MANUAL. 

to the discharging pallet during the dumb vibration, with an 
imperceptible resistance, and without moving the detent at all. 
It cannot yield in the opposite direction, because the horn or 
nose n of the detent supports it behind, near its point, so that 
when the discharging pallet hits it and moves it back it carries 
the detent back with it, and so carries the locking pallet out of 
the wheel. The impulse pallet also swings past the teeth with- 
out touching them during the dumb vibration, at the termination 
of which the balance begins another acting or wipidse vibration. 

(486.) When the discharging pallet now hits the gold spring, 
it carries that and the detent back, thus moving the locking 
pallet out of the wheel and letting it advance, and then lets the 
detent spring back to its place, ready to lock the next tooth. 
When the wheel was unlocked^ a tooth dropped on to the impulse 
pallet, //, and gave the balance an impulse as before, then the 
wheel was again arrested and locked by the locking pallet. 
The intersection of the gold spring and the discharging pallet is 
such that the balance moves about 5° to unlock the escape wheel. 

(487.) In beat. — When in beat, the parts should stand as fol- 
lows, in the usual construction of chronometer: when at rest, 
and perfectly free, the balance requires to be turned the same 
distance in either direction, to enable the unlocking spring or 
the detent to escape. 

(488.) To test the beat. — Allow the balance to come to a free 
rest, with the escape wheel locked. The end of the gold spring 
should be close to the back side of the unlocking pallet, i.e.., the 
side nearest the escape wheel, and the impulse pallet should 
stand just opposite the point of a tooth, the faces of both being 
in a radial line to the balance axis. 

(489.) Slowly move the balance back till the gold spring 
drops off the discharging pallet, note the distance moved, and 
bring the balance back to the point of rest. Then move the 
balance the other way till the gold spring (and detent) again 
drops, note that distance moved, then let the tooth escape. 
The two distances should be equal. 

(490.) Test by starting. — If the watch is in beat, it should start 
going if you move the balance in either direction, as above, and 
liberate it at the instant that the drop occurs. Test it in both 
directions. If the distances are equal but the watch fails to 
unlock when liberated in the first position, the unlocking is too 
difficult, for some reason, which you should discover and remedy; 
if it fails to start off when liberated in the latter position, the 
impulse roller may be too small, the balance too heavy for the 
motive force, there may be too little drop on the impulse pallet. 



THE WATCH ADJUSTER'S MANUAL. 205 

Examining the Escapement. 

(491.) The escape wheel. — See if the points of the teeth are 
straight, smooth and vertical. See if they are equal, by moving 
the balance from the point of rest slowly forward till the tooth 
drops on the impulse pallet, then backward till the tooth drops 
off, and note whether the intersection is safe, i.e.^ whether the 
tooth laps far enough on the pallet i p. You can judge some- 
what by the distance moved backward to enable the tooth to 
pass off. If the distance is very small, the intersection is 
shallow; but if large, while the intersection will be deep enough 
for safety, it may be so deep as to cause danger of setting (499). 
Try this with all of the teeth; if some intersect more deeply 
than others, the teeth are not equal in length, or have been bent 
or injured. If some do not intersect enough for safety, catch 
on the corner of the pallet, or miss it entirely, the wheel must 
be corrected or replaced; or, if the error is slight, turn the 
impulse roller on the staff to bring the pallet a little towards 
the line of centers (of balance and escape wheel) to get a little 
deeper and safer intersection. 

(492.) To test the clearance of the escape-ivheel teeth. — The watch 
being in beat (487) and running, hold it up to a strong light in 
such position that the balance falls towards the escape wheel, as 
closely as it can; there should be just visible clearance between 
the teeth at 2 and the edge of the impulse roller, and between 
the teeth, z, and the point of the impulse pallet // when they 
are just opposite and nearest together. If difficult to see the 
latter clearance, hold the balance still with the pallet opposite 
the tooth and examine. The light should be barely visible 
between them. If too close, make the end of the pallet jewel 
more bevelled, so it cannot touch the tooth. 

(493.) The clearance should be equal in both places, i and 
2. If it is not, knock the foot b of the detent towards or from 
the roller i p to make them so. Moving the detent also moves 
the locking, and so changes the position of the teeth when at 
rest, or locked. 

(494.) If the clearance is too great (more than required for 
safety) there will be too much drop off the pallet and onto the 
locking, and the impulse will be wasted; and the drop onto the 
pallet will be less secure. If the clearance is excessive, the 
impulse pallet i p should be set out further from the roller cen- 
ter to bring it nearer to the teeth at i. 

(495.) Correct impulse action. — When properly adjusted as 
directed, and running, the impulse pallet will move 5° from its 



206 THE WATCH ADJUSTER'S MANUAL. 

point of rest before the wheel is unlocked, and will have moved 
still further before the tooth / overtakes it to give the impulse. 
When the tooth reaches the pallet //, the circumferences of the 
roller and the wheel will intersect sufficiently for the tooth to 
lap well onto the pallet and give a safe contact. At the other 
extreme of their intersection the tooth slides off the pallet, and 
the wheel is then locked with the tooth 2 just clear of the edge 
of the roller. 

(496.) The drops. — There are two drops, the drop of the 
driving tooth i from the position of rest till it strikes the im- 
pulse pallet, and a small drop, from the position of leaving the 
pallet at 2 to that of locking. The former is the engaging drop, 
the latter the disengaging drop. These drops are very important, 
as their extents affect not only the safety of the intersection and 
the useful amount of the impulse, but also the time and the 
liability of the watch to vary or to stop. When " the drop" is 
spoken of, only, the engaging drop is meant. 

(497.) Extents of the drops. — When the arrangement is as de- 
scribed, (487, 492,) the engaging drop will generally be about 
10°, and the disengaging drop should be but little more than is 
required to give the tooth proper clearance. The 10° is the 
distance the balance has moved, from the instant the tooth was 
unlocked till it overtook the pallet. In the case of a balance 
one inch in diameter, 15° would be ^ inch on its rim, and 5° 
would be a little less than -^ inch. For a smaller balance, the 
distance would be proportionately less. In any case the dis- 
tance is small, and requires careful observation by the workman. 
The total intersection of the circle described by the point of the 
pallet (by the circle of the points of the teeth) is generally 45° 
for marine chronometers and about 35° to 36° for pocket chro- 
nometers. This is reduced slightly by the allowance for clear- 
ance, etc., so that the distance moved by the balance rim 
through the entire arc of intersection, as in testing the beat (487), 
would generally be less than \ inch. If we allow 5° for clear- 
ance, 10° for engaging and 5° for disengaging drop, there would 
be only 15° left for the actual contact while driving, and then 
supposing the impulse roller to be \ inch in diameter, the con- 
tact would continue through only ylo" '^^''^^ ^^ ^^^ edge of the 
roller, and at the balance rim it is only \ inch, showing how mi- 
nute the action is, and the perfection of adjustment required. 

(498.) The engaging drop. — Some workmen put the pallet more 
than 5° in advance of the tooth, and some have it less, thus 
increasing or lessening the drop onto the pallet. If the balance 
vibrations are large, and there is danger of overbanking or run- 



THE WATCH ADJUSTER'S MANUAL. 207 

ning (499), an increase of the drop will lessen the impulse 
given, and reduce the vibrations; if the vibrations are too small 
and sluggish, lessening the drop will increase or strengthen the 
impulse and enlarge the vibrations. But the drop should not be 
changed from the correct amount, as stated in (499), without 
good reason. 

(499.) If the engaging drop is too great, the balance vibra- 
tions may be so reduced as to be liable to set, especially if the 
motive force is weak and the balance heavy. If the drop is too 
short, there is danger of the tooth missing the pallet, or catch- 
ing on its corner, from the pallet not being far enough in 
advance to make the intersection of proper depth for safety; or, 
if the tooth strikes the pallet safely, the balance vibrations may 
be so enlarged that shaking or carrying will easily cause over- 
running. The engaging drop is changed by turning the impulse 
roller on the balance staff, towards the line of centres to increase 
the drop, and from it to lessen the drop. 

(500.) The disefigaging drop. — There can hardly be too little 
drop off the impulse pallet, provided that the tooth 2 after the 
drop stands far enough from the roller to safely clear its edge 
and the point of the pallet // during the dumb vibration, (485.) 
But the drop may be too great, causing waste of the impulse, 
which is expended upon the locking instead of on the impulse 
pallet, endangering the security of the locking, causing buckling 
of the detent, etc. If the clearance is correct and equal (492, 
493), the excessive drop can only be caused by the impulse pal- 
let not projecting out far enough, letting the tooth off too soon 
at 2. If the pallet clears the tooth properly when at rest (492), 
but the second tooth 2 is too far from the roller edge, the lock- 
ing stone and detent may require moving up towards the bal- 
ance, to bring the tooth 2 nearer to the roller edge. If this 
moves the other tooth i too far from the point of the impulse 
pallet, the pallet must be set further out in the roller, to get a 
safe intersection (491.) Possibly a larger roller would most 
easily secure a safe intersection of pallet and tooth during the 
impulse and lessen the disengaging drop. 

(501.) hnpulse roller. — In marine chronometers the diameter 
of the impulse roller is usually half that of the escape wheel, 
(at the tips of the teeth,) but in pocket watches the roller is 
larger, to lessen the danger of setting, and to increase the con- 
trol of the balance by the motive force. Whenever necessary 
(491,500), it can therefore be safely enlarged. The point of the 
pallet comes just to the circumference of the roller, which is set 
as closely in the escape wheel as will allow a safe clearance (492). 



208 THE WATCH ADJUSTER'S MANUAL. 

When the roller is rather small there is more danger of mislock- 
ing; if it is rather large, there is less danger of setting, but the 
intersection of tooth and pallet is more shallow and less secure, 
and the angle of impulse is lessened. The roller edge must be 
highly polished, vertical, concentric with the balance, and free 
from rust. 

(502.) Proper size of escape wheel and ifnpulse roller. — The pro- 
portions adopted by an eminent English maker of pocket chro- 
nometers, the late Mr. Walsh, were as follows: With a fifteen- 
tooth escape-wheel, the ratio of the radius of the wheel to the 
center distance (centers of balance and wheel) was as 65 to 100. 
By measuring the center distance with the depthing tool, the 
proper radius for the wheel can be easily calculated. Or, if a 
sector is used, a circle drawn with the depthing tool after taking 
the measurement as above can be set in the sector at the looth 
division, and the escape-wheel diameter is given at the 65th 
division. This gives a rather large wheel, which he preferred, 
as it more quickly checked the balance in case of overrunning, 
by the pressure on the roller edge. After allowing for drop and 
unlocking, the escaping arc would be about 43°. Other makers 
use other proportions, which must of course be followed in 
working at their watches, but the above will be a guide to show 
what proportions have given excellent performance. 

(503.) The crescent. — The crescent should be deep enough to 
prevent the point of the tooth bottoming in any position. The 
portion r, in front of the pallet, (about two-thirds of the whole,) 
should be wide enough to prevent any danger of the tooth hit- 
ting its corner, when starting to overtake the pallet, but not so 
wide that a second tooth could get into it while one was on the 
pallet. The intention in that case is that the second tooth 
should butt on the edge of the roller to the left of r, and be 
stopped there. That is very likely to damage the tooth, as it 
comes so near to passing by, and the engaging friction on the 
roller tends to wedge and force it by. It would seem better to 
make the crescent just wide enough to prevent the driving 
tooth from hitting the corner when starting, and then cut a 
notch in the roller edge, to the left of the hollow c and beyond 
its corner, like another pallet i p^ of steel. This would save the 
tooth from injury, and no great harm could be done by giving 
the impulse upon //, instead of on the true pallet //. 

(504.) The portion of the crescent behind the pallet, c\ is 
intended to catch the tooth if it slips by the pallet, and prevent 
it getting through. But that does no real good, and is likely 
to damage the point of the tooth. It would seem better to 



THE WA TCH ADJUSTER'S MANUAL. 209 

form that corner //, with an upright or radial face, like an- 
other pallet, to save the tooth from injury, and it would also 
get the impulse nearly as well as on the pallet //. The faces 
of these two false pallets should of course be radial and well 
polished. In case the wheel was accidentally unlocked either 
one or the other of them would be pretty certain to catch the 
tooth, and without danger of injuring it. 

(505.) The locking. — Locating the locking stone properly is 
the most important point in setting out the escapement. The 
face of the locking should have a perceptible draw on the tooth, 
and this is indispensable in the pocket chronometer, for if the 
draw is not sufficient to keep the locking to its place the watch 
will be utterly unreliable for carrying. It serves to keep the 
spring detent from being jarred off the banking, and the pivoted 
detent from leaving it by rebounding after striking it. But of 
course it must not be so great as to make the unlocking diffi- 
cult. The angle of draw should be about 10° in marine chro- 
nometers and 12° to 15° for pocket watches, or even 18° when 
the detent does not remain securely against the banking (509.) 
The security should not depend altogether on the draw, but be 
aided by the stiffness of the detent spring, and by the tooth 
having a safe depth of locking on the stone. When the face of 
the locking stone is much inclined it should be observed that 
turning the banking screw to adjust the depth of locking will 
also alter the clearance of the teeth at the impulse roller, (492,) 
and the clearance should afterwards be examined. 

(506.) The detent. — The spring detent is considered best for 
marine chronometers, but many workmen prefer the pivoted de- 
tent for pocket watches, with quick trains. The spring should 
be stiff enough to bring the detent to its place against the backing 
in time to catch the next tooth, but not so quickly that the pipe 
will hit the point of a tooth before it has had time to get out of 
the way after unlocking. To prevent this, it is customary to 
carry the locking stone as far out of the wheel as it moved to 
unlock the wheel, i.e.^ as far as it has moved into the wheel to 
lock it, making double the actual unlocking distance. If the 
spring is stiff, or the detent light, that may be necessary; in 
other cases a less distance might answer. The further a detent 
needs to be carried back in unlocking, the stiffer its spring must 
be in order to bring it back to its place in time. The detent 
itself must not be too slender and liable to bending; the longer 
it is, the heavier it must be to give it rigidity, and the spring 
must be stiffer to move it quickly — both of which are objection- 
able. 

14 



2IO THE WATCH ADJUSTER'S MANUAL. 

(507.) The pivoted detent should be very carefully poised. Its 
recovering spring is a spiral, similar to the balance spring, but 
having only three to five coils. Its stiffness can be adjusted by 
turning the collet on the detent staff, or by moving it through 
the stud, till it controls the detent briskly enough. The bank- 
ing must be very carefully adjusted with a pivoted detent. Ex- 
amine to see if it rebounds from the banking instead of remain- 
ing against it, especially if the detent is light, or is so slender 
that it springs and trembles. Get the light so that you can see 
any interval between the detent and the banking, use a power- 
ful glass, and run the watch with the mainspring fully wound 
up to get the heaviest blow of the tooth on the locking. Also 
try this, held so that the spring-detent falls //-^//z the wheel. If 
there is a marked interval between the banking and the detent 
while the tooth is locked, it maybe due to the recovering spring 
being too stiff, the detent carried too far out in unlocking, not 
enough draw, lack of poise, the detent too slender for the blow 
of the teeth, springy, etc. 

(508.) Examining the detent action. — Examine (both pivoted 
and spring detent) while the watch is running, to see that the 
detent spring S or the detent itself does not yield under the 
blows of the teeth and bend, buckle or tremble, nor spring and 
vibrate when it flies to the banking, nor fail to rest safely 
against it (507). See that it acts lively, and gets back to its 
place in time. This might be tested in very important cases by 
sticking a slip of card or thick paper on the face of the locking 
stone. If the tooth locked safely on that, it would show that 
the locking stone got to its place considerably before the tooth. 
See that the tooth locks far enough on the face for safety, but 
not too far, for that would make the unlocking difficult. This 
can be tried as directed for the "test by starting" (490,) or in 
any of the other ways mentioned. 

(509.) Testing the safety of the locking \^\\y\ spring detent. If 
the detent is long or heavy, or the spring weak, hold the move- 
ment so that the detent is b€loi.v the escape wheel and tends to 
fall from it, then jar it while running, to see if you can shake 
it from its place and unlock at the wrong time. In doubtful 
cases, try this repeatedly, with the balance still, to see if the 
locking stone can be shaken from under the tooth, or partly 
out. (If shaken out, the watch will probably start.) If so, 
the detent may be too heavy, or have too little draw on the 
tooth, or the point of the tooth may be bent or injured so as to 
neutralize the draw, or the locking of the tooth may be too 
shallow on the stone //. The spring must not be too stiff, nor 



THE WATCH ADJUSTER'S MANUAL. 21 1 

the draw too strong or the locking too deep, as it would make 
the unlocking hard, and both affect the timing and promote 
setting (570). 

(510.) Setting the hands back is very objectionable, and even 
dangerous, with the chronometer. The tooth 2^ which has just 
dropped off the pallet, may catch in the crescent, behind the 
pallet, during the dumb vibration, and butt, marring the point, 
or bending the tooth, or even breaking off the balance pivot; 
or if the tooth rests on the roller edge and the intersection is 
rather shallow, or if it hits on the end of the impulse pallet, the 
same result may follow; and the greater the force with which 
the hands are moved, the more risk of injuring something. 
This applies not only to setting the minute-hand, but also the 
seconds-hand. Even stopping the seconds-hand by putting 
something before it, on the dial, and holding it till a certain in- 
stant, for the purpose of setting the watch, is equally danger- 
ous. Aside from the probability of pushing it backward in 
spite of all your care, is the risk that when the hand is liberated 
the tooth may meet the roller edge or crescent or pallet in such 
a position as to damage something as already described. For 
instance, suppose that when you let loose the seconds-hand, and 
the tooth jumps forward, the balance is making its impulse vi- 
bration, />., both the balance and the wheel are moving in the 
same direction, at full speed, and the point of the tooth hap- 
pens to land on the end of the pallet, or at a shallow point in 
one end of the crescent, say, at the left end of r, or right end 
of c\ a bent or blunted tooth is certain, and a bent or broken 
pivot very probable. If the truth was known, the poor per- 
formance of many a good watch, after being repaired by a good 
workman, could be traced to this very cause. 

(511.) Taking off or putting on the haitds^ — and especially the 
seconds-hand, of a chronometer, is also an operation which 
must be properly performed, or injury will be done. In either 
taking the hand off or putting it on, there must be no pressure 
forward or backward, but it must be lifted directly upward or 
pressed directly downward. If it is twisted backward, the re- 
sults named in the preceding section will follow; if twisted for- 
ward, the pressure on the locking pallet may bend the tooth, 
loosen or break the pallet jewel, bend, twist, loosen or even 
break the detent. If the pallet // was not very firmly secured 
in the detent pipe, the pressure may tear it loose and turn it in 
the pipe, so as not only to take away the draw, but even to in- 
cline the locking face the wrong way. Then the wheel gets the 
habit of slipping off the locking and catching on the impulse 



212 THE WATCH ADJUSTER'S MANUAL. 

roller, and may soon be ruined; or, if the fault is not quite seri- 
ous enough for that, the watch is unreliable for time and con- 
demned as " no good," when there may be really nothing wrong 
except as above described. 

(512.) Tool for putting hands on. — In putting on a seconds- 
hand, bring the balance to rest., with the tooth locked to hold it 
still; put the socket of the hand on the pivot just far enough 
to stay as you place it, but not at all tight, adjust it to point 
exactly to the mark at 60, and then with a long mahogany slip 
press it down a little — all without starting the watch. If not 
far enough, press it on a little further; not enough to be too 
tight, but so that you can press the extreme end forward a lit- 
tle without displacing it — just tight enough not to be loose. 
The mahogany slip should be six inches long, to give a good 
handle to hold it b}'-. with the other end tapered down to \ inch 
wide and y*g inch thick, bevelled off from the top surface. 
Grasping this securely in the hand, rest the edge of the move- 
ment or case against the thumb and forefinger as a fulcrum, and 
press the end on the socket of the hand. In this way a direct 
downward pressure without twist is easily obtained — the length 
of the handle preventing any twisting at the working end. To 
take the hand off, a long-handled tool like a tack lifter should 
be used in a similar way. Of course, any other means will do 
which will secure equal safety, but those described will be found 
easy to make and as good as any. (See Hands and Dial., in 
Index.) 

(513.) Other points. — This chapter does not give all the faults 
which may be present, but it will give the workman an idea of 
how the parts should be, the effects of errors and of changes, 
and how to secure any desired results. He will not need to make 
so many separate tests as are described, but each one has been 
treated by itself in order to make the object in view perfectly 
clear. In practice, a single observation may answer for deter- 
mining a number of different points. But it w^ould be better to 
make each test described, and many others, than to overlook 
some point in order to save time. The thorough way is the only 
safe one, and is generally also the quickest. 

(514.) Further details will be found under other headings ap- 
propriate to the chronometer. Details of making, fitting and 
testing cylindrical hair springs of course refer to the chronome- 
ter; as regards the compensation balance, they apply to the 
chronometer equally with the lever; also, the chapter on mag- 
netism, etc., and the portion of the book treating on the various 
adjustments. 



PART SIXTH. 



THE ADJUSTMENT FOR ISOCHRONISM, 



CHAPTER XXIX. 

ISOCHRONISM. 

(515,) The isochronal adjustment. — We now come to the final 
adjustments of the hair spring for the purpose of insuring that 
the yibrations of the balance, whether they be great or small, 
shall always be accomplished in equal times, when the spring is 
said to be isochronized or adjusted for isochronism. I have al- 
ready given general directions for fitting springs, which, if 
followed, will prevent any very great errors of time from vary- 
ing arcs of vibration, and which, moreover, must be attended 
to before the last finishing touches, presently to be described, 
can be proceeded with. The isochronal adjustment of the hair 
spring is, without doubt, the most delicate and least understood 
operation the watchmaker is called upon to perform. Many 
who talk and write most glibly about it do not appear to know 
even the meaning of the term. And upon considering their 
ideas we are forced to the conclusion that unless their practice 
is better than their theories, it is not worth much ; or else, if 
they do really understand the subject, they are purposely trying 
to lead others off upon a wrong tack, in order to keep their 
knowledge to themselves. But to this there are, of course, 
honorable exceptions. 

(516.) I do not propose to advance any new theories, but to 
regard it in a very practical light, as a merely mechanical prob- 
lem, requiring no profound knowledge, either scientific or math- 
ematical, but which may be satisfactorily solved by any watch- 
maker of ordinary skill and patience. And I shall endeavor to 
give all necessary instructions for doing so. Even if the work- 
man does not intend to undertake the isochronal adjustment, 
it is important that he should know how to discover whether 
the watches he buys and pays an extra price for as isochronized, 
are so or not, for there is as much swindling of ignorant dealers 



214 THE WATCH ADJUSTER'S MANUAL. 

on *' isochronal hair springs" as on " compensation balances, 
adjusted for heat and cold," of which not one out of a hundred 
so called are adjusted at all. 

(517.) Action of 7ion-isochronal springs. — If the hair spring is 
not isochronal, the watch will vary from correct time whenever 
the extent of the motion of the balance, or the " arc of vibra- 
tion," as it is termed, is changed. In a watch having a going- 
barrel the vibrations are largest or longest when first wound up, 
and become smaller as the motive power becomes weaker, so 
that during every hour of the 24 the watch may keep a percep- 
tibly different time. Some springs perform the short vibrations 
in less time than they do the long ones, while others do the re- 
verse. A well made and well fitted spring will not vary much 
from uniform time, while a spring that is misshapen, crooked, 
out of center, unevenly coiled or tempered; that has been 
scraped, ground, much bent, or is very soft, will vary some- 
times several minutes during the day, although it may be some- 
where near right at the end of the day. Every change of the 
arc of vibration caused by jarring, carrying, keeping it in differ- 
ent positions or different temperatures, irregular winding, poor 
oil, dirt, etc., causes it to vary, so that for accurate timekeep- 
ing it is valueless. 

(518.) In duplex and cylinder escapements the resistance to 
the momentum of the balance caused by the pressure of the es- 
cape wheel upon the roller or cylinder, is greater or less in pro- 
portion to the greater or less motive force, and therefore these 
escapements are in some degree self-compensating for irregular 
motive forces. Yet they generally do vibrate further when first 
wound up. In English levers and chronometers the fusee and 
chain are employed to equalize the motive power. But, to do 
this accurately, the fusee must be cut in conformity to the vary- 
ing strength of the particular mainspring used, which is seldom 
done, as is shown by the varying arcs. When that mainspring 
breaks or another is substituted, whose strength increases in a 
different ratio, the fuzee cut for the original spring does not suit 
this one, and does not equalize its force. But were it so, the 
friction upon the balance pivots in different positio7is is another 
disturbing influence in all watches. And even if the watch is 
adjusted for positions, the thickening of the oil, accumulation 
of dirt, etc., by running, causes the vibrations to gradually di- 
minish. 

(519.) As it is practically impossible to prevent the arc of 
vibration from varying more or less, it is necessary in fine 
watches, after reducing that variation to the smallest possible 



THE WATCH ADJUSTER'S MANUAL. 215 

amount by mechanical means, to adjust the hair spring within 
those limits, so that no error of time shall result from such un- 
avoidable changes of the arcs of the balance. This adjustment 
or isochronizingof the hairspring can be done in different ways, 
which we shall consider at some length. But before undertak- 
ing this, and even before we can safely test our spring to see 
what and how much adjustment it requires, there are certain 
other points to be attended to. 

(520.) Requirements of isochronism. — Besides observing the in- 
structions already given for the correct forming and fitting of 
the spring itself, the balance and the lever must be perfectly 
poised; the balance, spring, lever, and all other parts in the 
watch, even the springs in the case, must be free from magnet- 
ism; the movement must be in good condition to transmit the 
motive force uniformly to the balance ; the escapement particu- 
larly must be as perfect as it can be made; the end-shake of the 
balance, lever and escape-wheel no greater than is necessary to 
give freedom of motion, so that there can be no material change 
in their relative positions; the pivots of the lever and balance 
staffs well fitted to their jewel holes; the lever pivots well pol- 
ished and free from any " binding" in any position of the move- 
ment; the balance pivots straight, hard and round, well polished, 
as small as is consistent with strength, their shoulders well clear 
of the jewels, and the balance not running too near the plate, 
bridge or any other part; the hole jewels thin and the holes 
round and finely polished; the holes not perfectly cylindrical, 
but a little rounded out or enlarged towards each end, to dimin- 
ish the extent of surface in contact with the pivots, and prevent 
any possible binding by either the jewel or pivot not being set 
exactly true, as well as to lessen the adhesion of the oil to the 
pivot; and in lever watches the ruby pin must be perfectly firm 
in its place and vertical, or parallel to the balance axis, and the 
slot in the end of the lever polished and well fitted to the ruby 
pin. Full details of the special requirements of each kind of 
escapement are given in the chapters devoted to that subject. 
(See Part Fifth.) 

If all this is not the case, it should be made so as nearly as 
possible, after which there is a certain order to be observed in 
our further proceedings. 

(521) Common notions about isochronism. — Most workmen have 
an idea that isochronism is some mysterious property of the 
spring which will enable it to overcome irregularities and diffi- 
culties and make the balance " come to time" in spite of them. 
Now that is just as incorrect as to say that it is one of the prop- 



2l6 THE WATCH ADJUSTER'S MANUAL. 

erties of a pivot to fit its jewel hole. It will fit the hole after 
it is made to fit, and not until then. So, a hair spring is iso- 
chronal after we have isochronized it, and not before. That is 
to say, after we have adjusted the length and shape of the 
spring, so that, under the effects of all disturbing influences 
acting upon it while the watch is going, it will make unequal 
vibrations in equal times, it is isochronized, or isochronal. Just 
as we say, after we have fitted the pivot, "it fits." But the fit 
is not a " property" of the pivot, nor is isochronism a property 
of the hair spring. It is simply a term representing a certain 
condition of being adjusted to act in a certain way under certain 
circumstances. But if those circumstances are changed one 
iota, there is no property or power in the spring to vary its 
action to suit that change, or correct its effects. Whatever pe- 
culiarity of action it may have as the result of our manipulations, 
that action is unvarying. If we want it to overcome certain 
difficulties, we must alter it till it does overcome them. Hence 
the spring should be isochronized with the frictions and all other 
influences, good or bad, which it is desired to neutralize, acting 
precisely as they will when the watch is finished and passed over 
to the customer. 

(522.) Testipig the isochronism. — Premising that all previous 
requirements have been properly attended to, we are ready to 
test our hair spring to see whether it is isochronal, and if not, 
in which direction it errs and how much. This is done by caus- 
ing the arcs of vibration to vary considerably, in the manner 
that is most convenient, and accurately observing the rate of 
the watch for an equal period with the long and with the short 
vibrations. 

The various methods of varying the amplitude of the vibra- 
tions will be described in Chapter XXXVI, sections (671-673.) 
But in whatever way they may be changed, if we find that the 
watch keeps the same time while running 4, 6 or 12 hours with 
the long vibrations, as during the same period with the short 
ones, the spring is already isochronal. But generally the watch 
will run slower with the long vibrations than with the short 
ones. In some cases the difference may be only a second or 
two — barely perceptible; in others, it may be several minutes. 
If the variation is considerable, it is better to repeat the test 
before making any change in the hair spring, to ascertain whether 
it is not due to some irregularity in the action of the movement. 
For it is useless to attempt to isochronize the spring unless the 
movement is in good condition. 
X (523.) During these trials the watch should be kept in the 



THE WATCH ADJUSTER' S MANUAL. 217 

same position, (generally dial up,) and at the same temperature, 
as otherwise the effects of changes of position and of tempera- 
ture would be confounded with the normal action of the spring 
in different arcs, and mislead the workman. The compensation 
for heat and cold is no part of the duty of the hair spring, but, 
on the contrary, the adjustment of that compensation must coun- 
teract the effects of heat and cold upon the spring. It must 
therefore be kept at a uniform temperature while being iso- 
chronized. 

(524.) Quick test for isochronism. — Just here I will mention a 
"quick and easy method of testing the isochronism of a spring," 
widely taught and highly indorsed : — " Insert four pins in the rim 
of a balance, about a quarter of an inch long and equidistant 
from each other. Then fix a temporary detent by the side of 
one of the pins when the spring is free. Then turn the balance 
one quarter around, and let the next pin rest against the detent, 
and find the weight that will just balance the force of the spring 
when placed on the pin. Turn the balance another quarter 
around, and if the weight that pin will sustain is just double the 
former, the spring is isochronal. Turn the balance to the third 
pin and the weight should then be three times the first. If the 
spring will not sustain that weight, it will be too slow in the 
long vibrations. If it sustains more than that, it will be too 
fast in the long vibrations," and so on. 

This is substantially equivalent to the "elastic balance" de- 
vised by le Roy and used by all of the older horologists for 
measuring the force of balance springs and their divergence from 
a uniform increase of strength. 

(525.) No true test except timing in the watch. — Such a test is 
only approximately true in theory, and w'orthless in practice. 
There is no practical method of testing the isochronism of a 
spring except by testing it in the watch, in the precise circum- 
stances for which it is required to be isochronal, by timing it as 
already described. Were the strength of the spring the only 
factor to be considered, this test would be theoretically correct 
for a perfect spring. But since all escapements do in some de- 
gree disturb the oscillations of the balance, and different escape- 
ments do this very differently, it must be impossible to isochron- 
ize a spring independently of the escapement, i.e.^ otherwise 
than in the watch to which it belongs. And this conclusion is 
the more evident when we consider the many other disturbing 
influences, of which we cannot foresee the nature, degree or 
manner of their occurrence, but which must necessarily be pro- 
vided for. The principal use of the elastic balance and spring 



2i8 THE WATCH ADJUSTER'S MANUAL. 

gauges, in connection with isochronism, is to find whether a 
spring, by itself, increases in strength in proportion to the angle 
of flexion. Any irregularity would indicate some flaw in the 
metal or other fault, and the workman would be saved from ex- 
pending labor and time on a worthless spring by thus discovering 
the fault at the start. 

(526.) Even were it possible to secure certain and definite 
conditions, and to know the exact form and strength of the 
spring adapted to them, the above test would be practically 
worthless from its clumsiness. A watch makes, we will say, 
432,000 vibrations in 24 hours. Now does any one suppose 
chat, by the above or any other weighing process, it would be 
possible to detect a variation from the proper progression in the 
strength of the spring, so slight that, after multiplying the 
effect it produces on a single vibration 432,000 times, it only 
causes an error of a few seconds more or less? It must be re- 
membered that the isochronal test has nothing to do with the 
actual strength of the spring, (which concerns only the rate,) 
but only with the correctness of the ratio in which it increases. 
The above "test" might possibly detect errors amounting to 
several minutes in a day, but such errors cannot occur if pre- 
vious directions for selecting springs have been followed, and 
any good workman would know that such a spring was unsuita- 
ble or defective, without any test at all. 

(527.) Comparing the results. — We will suppose that we set the 
watch at 9 a.m., and on running it for 12 hours with the long 
vibrations, its hands show 8 hours, 59 minutes, 45 seconds — 
and after setting again, it shows for the 12 hours with the short 
vibrations, 9 hours, 15 seconds, i.e.^ 15 seconds after 9 o'clock. 

Then there is a difference of 30 seconds — the long vibrations 
being slower than the short ones, or taking longer time to ac- 
complish them. This point must be clearly understood, to pre- 
vent blunders and improper alterations. Whenever the watch 
gains., it is because more than the proper number of vibrations 
have been made in the given time, therefore they are shorter 
and quicker than they should be. When the watch loses, less 
than the proper number are made, because each one takes longer 
than it should and the hands are not moved so far as they should 
have been. But it does not matter whether the times kept by 
the watch are faster or slower than the correct time, nor if our 
alterations make both of them faster or both slower than they 
should be. All that is necessary for these tests is to compare 
the two times with each other., to see whether the short vibrations 
are quicker or slower than the long ones. And the only use of 



THE WATCH ADJUSTER' S MANUAL. 219 

correct time, at present, is to enable us to compare the two re- 
sults and know the exact difference. 

(528.) What is isochronism ? — The question naturally arises why 
the long vibrations are slower or quicker than the short ones, 
when the length of the hair spring is exactly the same in each 
case. The prevailing theory is that the isochronism of the 
spring depends on its being of a certain length in proportion to 
its strength, and if it is longer than that it will lose in the long 
vibrations, but if shorter, it will gain in the long vibrations. 
This theory is credited to Pierre le Roy, and has the indorse- 
ment of a host of other eminent authorities from le Roy's day 
to this. Yet it is not true, for a spring will have several differ- 
ent isochronal points or lengths, while it is not isochronal at any 
intervening points. In fact, there appears to be an isochronal 
point somewhere in every coil, provided that its length is not so 
great or small as to interfere with its free and proper action. 
The theory has the appearance of truth, because, when the iso- 
chronal point is found for the particular spring, if it is then 
lengthened it will lose, and if shortened will gain, in the long 
arcs. But that isochronal point depends upon many other con- 
ditions besides the proportionate length and strength of the 
spring. The number of coils and manner of coiling, the mode 
of attachment to the stud and collet, the shape of the terminal 
curves at the ends, are among the conditions in the spring itself 
which may either improve or destroy its isochronism. And out- 
side of the spring are many others The truth is that a spring 
which has been perfectly isochronized is so only for the precise 
conditions for which it is adjusted. 

(529.) Another definition of isochronism as follows: "Iso- 
chronism is a certain correspondence or relation between the 
proportions of a hair spring and of a balance, and such that 
under proper conditions the spring will move the balance through 
greater or smaller arcs in equal times." This is very good so 
far as it goes, but it takes into consideration only the spring 
and the balance. But, as already shown, there are many other 
points which theoretically and really are concerned in bringing 
about the complete result we call isochronism. 

(530.) Modifying i}ifluc?ices. — It would be interesting to go fully 
into the theoretical consideration of the conditions of isochro- 
nism, the effects of all the modifying influences upon the extent 
and the time of the vibrations. But to do so would require 
several chapters, and I will content myself with a brief classifi- 
cation of a few of the more prominent influences and their 
practical effects. The first class comprises any friction or re- 



220 THE WA TCH ADJUSTER'S MANUAL. 

tarding influence which is equal and continuous throughout the 
whole or nearly the whole of the vibration, as the friction of the 
pivots, thickening of the oil, pressure of the duplex or cylinder 
escape wheel against the balance axis, and the like. The effect 
of these may be to make the short vibrations either quicker or 
slower than the long ones, according to the conditions in each 
case, but generally they will be slower. 

(531.) There is another class of influences, the principal and 
type of which is the resistance of the air to the motion of the 
balance. This depends on the construction, weight, specific 
gravity and exposed surface of its parts, and it increases with 
the increase of the arc of vibration in the proportion of the 
squares of the velocities. That is, if one balance vibrates twice 
as far as another, and in the same time, the resistance of the 
air to the motion of the former would be four times as great as 
of the latter. But as the momentum of the balance also in- 
creases as the squares of the arcs, they therefore increase and 
decrease uniformly. Of course a smooth, heavy balance will 
meet with less resistance than a large and light one, with numer- 
ous screws, etc. But whether that resistance be great or small, 
whatever the amount may be, it will increase and decrease as 
the squares of the velocities. The effect is therefore greater 
as the amplitude of the vibrations increases, and makes them 
quicker. 

(532.) Thirdly, different escapements affect the time of the 
vibrations, because they interfere with the normal time which the 
spring alone would give, by breaking in at a certain point and 
giving the balance a push, thereby hurrying up its motion while 
in contact. So that the length of the time of contact, or angle 
of impulse, becomes a factor in the problem, as well as the fre- 
quency of these contacts — whether occurring at each vibration, 
or only alternate ones, as in the chronometer and duplex; and 
whether there is any recoil in the escapement, as in the duplex 
and cylinder escapements under certain circumstances. The 
power required to unlock the escapement, giving more or less 
of a check to the motion of the balance, is another factor; the 
fall or " drop" of the escape-wheel teeth against a cylinder or 
balance staff, urged on by the entire motive force, must at the 
instant of impact exert a checking influence. In the cylinder 
escapement the side pressure upon the balance axis is removed 
during the arc of escape, at the middle of the vibration, — an- 
other point to be considered. Escapement frictions retard the 
short vibrations more than the long ones. 

(533.) Lastly, there are the irregular influences, among which 



THE WATCH ADJUSTER'S MANUAL. 221 

may be mentioned unavoidable imperfections in the metal or 
form of the spring, unequal hardening or temper, imperfections 
in the balance, pivots, escapement, and others already men- 
tioned. A soft spring cannot be isochronized, and if it could it 
would not stay so. Even the mere bending of a spring, although 
it may have been restored to its former shape, produces an un- 
evenness of texture at that point, and the lower the temper of 
the spring the great is the effect of such treatment. If these 
spots are stiffer than the remainder of the spring they do not 
bend with the other parts, or not equally, and throw the spring 
out of shape; if they are not so stiff, they bend too soon and the 
same result follows. If a spring is let out at the stud, the 
crimp made where it was pinned will produce a stijff spot and 
interfere with uniform inflexion of the spring. A beginner will 
frequently render a spring worthless for isochronal adjustment 
by numerous changes and corrections. It should be bent as 
little as possible, and when necessary it should be done a little 
at a time and repeated, rather than bent too much and then 
have to take back a part. Many other disturbing influences are 
mentioned in Chapter XXXVII, on Position Faults. 

(534.) This class of influences no foresight can entirely pre- 
vent, nor can we know in what part of the vibration they will 
occur, or how great they will be, until we ascertain by actual 
test. No theory can avail against their occurrence nor do away 
with their effects. This can only be done, if done at all, by 
proceeding at once to adjust the springy in the direction indicated 
by the test, until success is attained or found to be unattainable. 
And, from what has already been said of the first three classes, 
it must be plain that, for all practical purposes, the workman 
will find that nothing further is necessary in the isochronal ad- 
justment than to secure the mechanical correctness of the differ- 
ent parts, and then to govern his proceedings entirely by the 
extent of the vibrations, and the tivies given during his trials, 
while actually adjusting the spring in the watch, to counteract 
the errors caused by frictions and all other disturbing influences. 



CHAPTER XXX. 

Why Springs are Isochronous. 

(535-) O^^ what does isochronism depend 2 — As we have seen, a 
great number of influences affect the isochronism of a spring. 
Some make the short vibrations quicker than the long ones, 



222 THE WATCH ADJUSTER'S MANUAL. 

Others have the contrary effect. A spring which is adjusted and 
made isochronous with one kind of escapement will not be so 
with a different escapement, nor with another watch having the 
same kind of escapement but made differently, nor even when 
made the same, with the exception that the balance has differ- 
ent dimensions. On the other hand, if a spring of a certain 
length, shape and temper is isochronous, we may substitute for 
it another spring exactly like it except that it is wider, and the 
latter will also be isochronous for the same arcs of vibration. 
It will be stronger than the former, in proportion to its greater 
width and will carry a balance which is heavier, but in other 
respects like the one carried by the former spring. 

(536.) Different opinions of the cause of isochronism. — It was 
formerly thought that if the strength of a spring increased in 
proportion to the angle of flexion, it would be isochronous. 
But it was soon discovered that that would secure theoretical 
isochronism, of the spring by itself, but not practical isochro- 
nism in the watch. The best authorities of the present day 
differ widely in their opinions as to the cause of isochronism. 
I have taken the trouble to bring their various ideas together 
for instructive comparison, while refraining in most cases from 
mentioning names. 

(537.) The original theory put forth by Pierre le Roy was 
that in every spring of sufficient extent there is a certain length 
where all the vibrations, long or short, large or small, will be 
isochronous, and that when this length is found, if you shorten 
the spring the large vibrations will be made in less time than the 
small ones, or, if you lengthen the spring the long vibrations 
will be slower than the small ones. 

(538.) Coming down to modern times, one school of adjusters 
claim that isochronism does not depend on the length of the 
spring, but is obtained by pinning it in even or complete coils, 
and avoiding fractional parts of coils between the collet and the 
stud. Another school holds that isochronism does not depend 
either on the length or method of pinning, but on giving the 
proper curvature to one or both ends of the spring, (/>., on 
terminal curves,) and that mere length has nothing whatever to 
do with isochronism. 

(539.) Another insists that length has everything to do with 
it, and that a spring which is too short will make the short 
vibrations in less time than the long ones, and vice versa, regard- 
less of its form. Another claimed that every coil had its iso- 
chronal point, and that if the spring was pinned there, the 
vibrations would be isochronal. Another holds that the length 



THE WATCH ADJUSTER'S MANUAL. 



223 



is the essential point, and that different lengths were required 
for different escapements, — a length which would be suited to 
one escapement would be quite unfit for another. Another 
explains that the different length of the spring has of itself 
no influence in correcting errors in isochronism, but the effect 
is due to the mechanical relation of the collet and stud being 
changed, i.e.^ the relative positions of the two ends of the spring 
are better adapted for causing it to vibrate synchronously. 
Saunier says, however, that it makes absolutely no difference 
what their relative positions may be; one may be over the other, 
or be at any angle whatever with it. 

(540.) Many practical springers and adjusters secure isochro- 
nism by putting the balance out of poise in such a way as to 
assist or retard the spring at the ends of its vibrations, while 
others correct errors of isochronism by putting the spring itself 
out of center, or making it excentric, instead of concentric, as 
others insist that it must be. So it goes. Every one of these 
methods secures good results 
in certain cases, adapted to it, 
but none of them succeed in 
all cases. 

(541.) The Phillips ' theory of 
the terminal curve. — If there 
is any one theory regarding 
isochronism which is more 
generally regarded with respect 
than others, it is probably the 
theory of terminal curves put 
forward by Prof. Phillips of 
the Polytechnical School, in 
Paris, in his treatise Sur le 
spiral r^glant. Prof. Phillips 
is a very able mathematician, 
and has developed his theory 
in detail, in accordance with mechanical laws — with such 
ability, in fact, that the most eminent horologists, as well as 
practical men everywhere, tacitly accept it as being unquestion- 
ably true. It will therefore be worth our while to examine it 
carefully, so far as may be necessary to understand it. 

(542.) £>iagraj?i of a Phillips' curve. — Fig. 27 is substantially 
the diagram given in his treatise. The circle represents the 
outer coil of the spring; the terminal curve leaves it at b, and 
curves through d to its end at e. At a is the center of the 
spring, and the position of the axis of the balance ; ^^ is a radius 




Fig. 27. 



224 THE WATCH ADJUSTER'S MANUAL. 

drawn through the beginning of the curve, and ah is one through 
its end. 

(543.) The conditiofis of the Phillips' theory are: (i) that the 
center of gravity of the terminal curve be must fall upon a radius 
which is at right angles to the radius passing through the begin- 
ning of the curve, or ba. The center of gravity of the curve 
must therefore be somewhere in the radius af^ (which is at right 
angles to ab^^ and, for the curve shown, the center of gravity is 
at c. (2) The distance ac must be to the distance ab, as the 
length of the radius ab is to the length of the curve bdie^ a 
proportion which we write thus: 

ab : bde \\ ac : ab^ 

which gives us the distance ae = -jl — This condition was ex- 
pressed in the treatise in a different way, viz. : that the distance 
ac must be a third proportional to the radius ab and the length 
bde of the curve. But the reader who is not versed in mathe- 
matics will understand it better when expressed the other way. 
(544.) Properties of a spriiig with such a terminal curve. — Prof. 
Phillips states that a spring having its ends formed into two 
parallel curves which satisfy the above conditions will have the 
following properties: 

1. The center of gravity of the spring will always be on a^ 
the axis of the balance. 

2. The spring will remain perfectly cylindrical and concentric 
with the axis a while coiling and uncoiling, and its strength will 
increase in proportion to the angle through which the balance 
is turned. 

3. The spring will never cause any side pressure of the bal- 
ance pivots in their holes. 

It will be observed that this theory is intended to apply more 
especially to cylindrical springs having a terminal curve on each 
end, and I will examine it first on that basis. 

(545.) The cetiter of gravity., with two curves, — Prof. Phillips 
says the center of gravity of the spring will be on the balance 
axis, if it is provided with " two parallel curves" such as de- 
scribed. Taking that statement literally, it is evidently an 
error, for if they are parallel, and one over the other, (as they 
must be if parallel,) the center of gravity of both of them would 
be at r, and not on the axis a. There are only two conceivable 
cases in which that statement can be correct: (i) The two 
curves «<?/ parallel, but exactly opposite. Fig. 28 illustrates this. 
In order that the center of gravity of the entire spring should 




THE WATCH ADJUSTER' S MANUAL. 225 

be on a, the centers of gravity of the two curves must fall in 
radii af and af which are exactly opposite, {i.e. in the same 
diametrical line,) and at points c and c^ which are at the same 
distances from a; in that case the center of gravity of the two 
would be on a. This would require that one curve should begin 
at ^, and the other at ^\ exactly opposite, and the lengths of 
the two curves must be precisely the same. It is very doubtful 
if any spring was ever made in that way. The distances ac and 
ac^ may be unequal, however, if the lengths of the curves are 
inversely modified, />., if the length of the first curve multiplied 
by ac is equal to the length of the other 
curve multiplied by ac^. The center of 
gravity of the weights at c and c^ would 
then be on a. It is stated that the two 
curves may be crossed or inclined at any 
angle to each other — but that would not 
be in conformity to Phillips' theory. (2) 
If the centers of gravity of the two curves 
do not fall on radii exactly opposite, as is 
shown in Fig. 28, the center of gravity of y\q.. 28. 

the spring cannot fall on a unless the dis- 
tance ac or ac^ is nothing; and according to the proportion 
given in section (543), if ac was nothing, ab must also be 
nothing, i.e.., the diameter of the spring would be nothing, 
which is impossible. 

(546.) Center of gravity., with one curve. — Breguet springs are 
often provided with curves similar to that shown in Fig. 27, and 
called Phillips' curves. The reader will also bear in mind that 
when the watch is running, one curve of the cylindrical spring is 
supported by the stud., so that the weight of only the other curve 
rests on the pivots. I will therefore consider the center of 
gravity of a single curve, supposing the body of the spring to 
be concentric and in poise. In the case of the Breguet spring, 
it does not matter where the center of gravity of the curve may 
be, because it is supported by the stud. The curve of a cylin- 
drical spring the weight of which rests on the pivots cannot 
possibly have its centre of gravity on the axis ^, (see Fig. 27,) 
if its length does not exceed a half turn, and in any of the 
forms ordinarily used it cannot be on the axis at all. Mere 
inspection of Fig. 27 will satisfy any one of that fact. 
This shows the propriety of the rule given in section (299), 
that the collet bar and the curve of the spring should be 
poised in position on the balance staff. It will be seen, from 
the foregoing considerations, that in forming terminal curves 
15 



226 



THE WATCH ADJUSTER'S MANUAL. 



it is perfectly useless to pay any regard to their centers of 
gravity. 

(547.) Securing conceiitricity and rcgulaj' progression of force. — 
Prof. Phillips states (544) that a spring having two parallel 
curves which satisfy the conditions in section {543) will remain 
concentric, will exert no side pressure on the pivots, and will 
increase in strength in proportion to the angle of flexion. If 
so, it is important. Suppose we modify the form shown in Fig. 
27, as indicated in Fig. 29, in dotted lines. The original curve 
is bid4e. One modification is b2d^e^ the other is bjdde. 
The center of gravity of each one is at <:, and each satisfies the 
conditions of Phillips' theory. Is there any reason for believing 
that either modification would cause the body of the spring to 
remain concentric, avoid side pressure, and increase in strength 

in proportion to the angle of 
flexion. If not, it follows that 
springs made in accordance 
with that theory are not invari- 
ably or necessarily isochronous. 
Even if they possessed the regu- 
lar progression in force, that 
would only secure a theoretical 
isochronism of the spring by 
itself, which is valueless, as 
only a practical isochronism 
which covers all peculiarities of 
the entire watch in action is of 
any real importance. 

(548.) So- called Phillips ' curves 
in use. — It appears, therefore, 
that the most of those who 
use so-called Phillips* curves, are blindly following a theory, 
they know not why, and without getting any benefit from 
it. They speak of "the Phillips' curve," and of it being 
"always the same," not knowing that there is no such 
thing as "the Phillips' curve," in the sense implied, of it 
having one particular shape. There are dozens of curves, 
having the most dissimilar forms, each of which is "« Phillips' 
curve," because it is made according to the Phillips' theory. 
But there is no one particular form which can be correctly 
called ^^ the Phillips' curve." Those who are using "the 
Phillips' curve " are merely imitating the form chosen by him as 
most convenient in illustrating his theory, and which I have 
reproduced in Fig. 27. But neither that fior any other form 




Fig. 29. 



THE WATCH ADJUSTER'S MANUAL. 227 

will suit all cases; it must be changed and "adjusted" to make 
it provide for all the peculiarities of the movement containing 
it. Hence all such fancy forms merely cause useless trouble in 
making and adjusting. A more regular form would be far bet- 
ter. The English, with their practical, common-sense methods, 
recognize this, and use more direct, simple and serviceable 
shapes for their curves. The perfection of their results affords 
ample evidence that they are correct in doing so. 

(549.) Old and new forms for Phillips' curves. — Twenty-four 
different shapes were originally shown, each of which would 
satisfy the conditions of Phillips' theory. On looking them 
over, we find almost every form, from the most regular to the 
most irregular. Some make a half turn, and others are from 
that up to a full turn. In some, the end of the curve is at the 
center of position of the spring, and in others at the outer cir- 
cle; others at -|- the distance from the center to the outside, or 
at -J, I", I", I" that distance. In some, the curve starts very grad- 
ually from the outer circle, in others abruptly, both kinds having 
the same length, ^ turn. The outer ends are generally pinned 
at a tangent to the radius passing through them, but some curve 
inward of the tangent, and others outward. It is stated that 
the curves at the two ends of the spring need not be alike, and 
they may stand at any angle with each other. I had intended 
to show some new forms which would satisfy Phillips' theory, 
and among them curves for pinning at one-half the radius of the 
spring and others to pin outside of the circle of the spring, as is 
done with the flat spiral. But the reader who has fully under- 
stood the foregoing descriptions can easily do that for himself. 
Those who feel interested can obtain Prof. Phillips' treatise for 
two francs, (in French,) and study it at leisure. What may be 
called the English curves will be treated in the chapters devoted 
to making terminal curves. 

(550.) Contradictory methods of securi7ig isochronism. — As is well 
known, we can secure isochronism by means of terminal curves, 
and equally well without any curves at all — merely using a 
straight piece of spring at the stud end, (called the isochronous 
stud (559,) or even without that — as in the flat spiral spring; by 
pinning in even coils, or in fractional coils; by a certain length, 
and without regard to the length; with the balance in poise, and 
out of poise; with the spring concentric, or excentric; by the 
regulator pins, and without any regulator; by pinning the stud 
end of the spring outside of the circle, or at half its radius; by 
changing the weight of the balance; by changing the shape of 
the screws in its rim; by changing the average motive force; 



228 THE WATCH ADJUSTER'S MANUAL. 

by changing the action of the escapement; by changing the size 
or the shape of the balance pivots; by changing the size of the 
collet; by changing the form of the inner end of the spring; by 
changing the direction of the spring as it leaves the stud; and 
in still other ways, as indicated in Chapter XXXI. 

(551.) The law of isochro7iism. — In view of these facts, the 
question again arises, on what does isochronism depend ? What 
is the action or principle or means which is really useful and 
indispensable? The law which evidently includes all conditions 
and all forces affecting the result is the mechanical principle 
that " the movements of a vibrating balance will be isochronal 
when the sum of all the forces impelling or retarding it increase 
in proportion to the angle of oscillation." This covers every 
force acting upon it, either to advance or retard it: the mo- 
mentum of the balance, and any lack of poise, or of truth in 
form or centering; the frictions of pivots, air, etc. ; the action 
of the oil, and of dirt; the effect of the escapement; the action 
of the hair spring, whether correct or otherwise, and all other 
influences. Some of them urge the balance forward, at the 
same time that others resist it. But the net result of all of 
them combined must be a force proportional to the extent of 
the vibration. When that is secured, this joint force will be 
doubled to propel the balance through double the angle of ro- 
tation, from the point of rest, and so with any other proportion, 
and the strength of the spring must be doubled to bring the 
balance back to the point of rest in the same time as before. 

(552.) The force of the hair-spring. — At the end of the vibra- 
tion, the spring draws the balance back ; while inertia, the 
various frictions, etc., resist it. The spring is the only force 
then acting to produce the vibration, and it must overcome all 
other influences. But, as the balance moves towards the center 
or point of rest, some of the opposing influences become less or 
disappear entirely, while others make their appearance, and then 
the disturbing influence of the escapement comes into play. 
Fortunately, the balance (if it has the correct proportions) is 
not controlled by these several influences. It acts as a store- 
house of energy ; whatever influence impels it onward is added 
to the force already stored in its mass; whatever resists it is 
subtracted therefrom, and the remainder is the net or active 
impelling force producing the vibration. 

(553.) Isochronal vibrations. — When the retarding and the 
propelling influences are practically equal, or when these irregu- 
lar or disturbing influences are extremely small in amount as 
compared with the regularly progressive force of the spring, or 



THE WATCH ADJUSTER'S MANUAL. 22g 

when that progression is not regular but is properly modified to 
counteract the disturbing influences, we have nearly or practi- 
cally isochronal vibrations. The foregoing explanations will 
show why the hair spring is but one factor, although the most 
important one, which has to be taken into consideration in 
securing isochronism, and why a spring which is perfectly iso- 
chronous by itself, or even when attached to a balance, may 
not be isochronous when running in the watch. It also shows 
that there cannot be any one form of spring, or any theoretical 
method of procedure, which will invariably secure isochronism, 
but the different escapements and the peculiarities of each 
movement must be allowed for. It is only after that has been 
done that we can have really isochronal vibrations. And even 
then it must be remembered that while theoretical isochronism 
is perfection, practical isochronism is a compromise, and there- 
fore only approximate. 

(554.) Sunwiary. — After we have considered all theories, all 
principles and laws, all influences affecting the result, and all 
the conclusions which have been arrived at by different persons, 
so far as they are generally known, what have we learned from 
them? Simply this: i. That there is such a condition as 
theoretical isochronism, which exists when the strength of the 
spring increases in proportion to the angle of flexion. 2. That 
theoretical isochronism is of no value or use whatever to us in 
adjusting a watch for isochronism. 3. That what we require is 
practical isochronism, i.e.^ isochronal vibrations when the 
watch is actually running. 4. That the only way yet known 
for securing practical isochronism is to adjust the spring by cer- 
tain empirical methods, derived from experience, until the vibra- 
tions are found to be isochronal. 5. That the true philosophy 
of the adjustment, i.e.^ how or why those methods make the 
vibrations isochronal, has never been explained. It is not 
enough to say that they adjust the spring in such a way that 
the propelling and retarding influences are equally balanced; or 
that, when the various influences are so balanced, the long and 
short vibrations will be made in equal times, for that is a sort of 
explanation which explains nothing. The question is, why are 
they performed in equal times? How does that balancing en- 
able a spring to do that ? 

(555.) Theoretical isochronism. — To make this point more 
clear, I show in Fig. 30 two arcs: the first from i to 2, repre- 
senting the short vibrations, and another twice as long, from j 
to 4^ for the long ones. Let us suppose that the balance vibrates 
through the lower arc, ///2, in one second. It is evident that, 



230 



THE WATCH ADJUSTER'S MANUAL. 




if it also vibrates through the arc j b 4 m one second, its pe- 
ripheral speed in the part i b 2 will be more than double what it 
was when making the short vibrations ib'2, of that length. 
This shows the fallacy of the common idea that it vibrates 
through the short arc in a certain time, and, when the arc is 
doubled, it first vibrates through the short arc as before, and 
then an equal additional amount of force is required to carry it 
through the additional distance. The fact is, that it not only 
performs the additional distance, but it also performs the original 
distance in less than half the time it did before. Now, is 

that accounted for or explained by 
saying that the propelling and the 
retarding influences are equal, or that 
double the force will carry the bal- 
ance through double the distance? 
Not at all, for that is merely theo- 
retical isochronism, of a free spring 
and balance without friction. In a 
watch, with its frictions and other 
faults, that statement would not be 
true, for double the force would Jiot carry it through double 
the distance, except in very rare cases. The distance might 
be more or less than double, according to the condition of the 
movement. 

(556. ) Practical isochrojiism. — The correct explanation of prac- 
tical isochronism is this: The true (/>. , practically) isochronous 
spring, — by itself or with the balance, without frictions, etc., — 
would always perform the long and short arcs in diffei-ent times 
— never in equal times; if it did, it could not possibly be isochro- 
nous. For example, let us suppose that we have a spring theo- 
reticallv perfect, i.e.^ its force increases exactly in proportion to 
the angle of flexion, and when run in the watch in such a way 
that frictions, position faults and the like could not affect the 
vibrations, it would perform the long and short arcs in precisel}' 
the same times, (555.) Then we find by trial that the frictions 
and other disturbing influences, when allowed to affect the mo- 
tion of the balance, retard it, so that the long vibrations are 4 
seconds per day slower than they were before, and the short 
arcs are 12 seconds slower — these influences being always more 
felt in the short arcs than the long ones. 

(557.) In the ordinary way of speaking, we would say that 
there was a loss of 8 seconds in the short arcs, because we would 
take the rate in the long arcs as the standard of comparison, 
and compare the rate in the short arcs with that. But in reality, 



THE WATCH ADJUSTER'S MANUAL. i-t^i 

both long and short arcs are retarded, as we would find if we 
could time the spring without being at all affected by frictions, 
etc. As it is, we cannot do that, and when we take the rate in 
the long arcs, that rate includes such effects of friction, etc., 
as are felt in the long arcs; and the loss observed in the short 
arcs is due to those frictions being proportionally more felt in 
the short than in the long arcs. We then proceed to adjust the 
spring to correct that loss. How do we do it? Simply by 
destroying the theoretical isochronism of that " perfect" spring, 
altering it so that it would (alone) perform the long and short 
arcs in different times, causing it to gain in both the long and 
short vibrations, but to gain most in the short ones, //// the gain 
of the spring balances the loss due to the frictio7is^ etc. Then the 
rate will be the same in both long and short arcs, the spring will 
be what is termed "isochronous," and we will have attained 
practical isochronism. 

(558.) Isochronous spring. — The proper definition of isochro- 
nous spring, therefore, is " a spring whose errors in different 
arcs and positions are equal to, and the reverse of, the errors 
caused by frictions and other disturbing influences." When that 
is the. case, the vibrations will be isochronal, the rate will be 
the same in different arcs and positions, and the spring will be 
truly "isochronous." The greater the errors to be covered or 
corrected, the greater must be the contrary errors of the spring, 
in order to balance them. They cannot be hidden or " cor- 
rected" in any other way. If the faults of the movement cause 
a loss of 8 seconds per day in the short arcs, and we alter the 
spring so that the watch then loses nothing at all, we have made 
the spring gain 8 seconds, so that its gain just balances that 
loss. On the other hand, if the disturbing influences cause the 
balance to accelerate in the short arc, the spring must be made 
to lose an equal amount, in order to balance it and secure an 
equal rate in the long and short arcs. Any talk about causing 
the spring to increase its force in a different ratio, etc., is 
simply nonsense. The spring has no occult properties, and it 
is not necessary to fall back upon such mysterious and meaning- 
less suppositions, when we have a plain, common-sense explana- 
tion, which common sense tells us is true. 



232 THE WATCH ADJUSTER'S MANUAL. 



CHAPTER XXXI. 

Methods of Securing Isochronism. 

(559.) Nu77ierous methods. — A great number of different 
methods have been proposed for isochronizing a hair spring, of 
which some are good, some not so good, some good for nothing, 
and some worse than nothing. I had prepared a list of over 
forty different methods of securing or varying the isochronal 
action of the spring, with the intention of describing each one 
in detail. But as only a few of them are employed in practice, 
and those which are used are capable of producing any effect 
which could be produced by the others, it was thought wise to 
devote the space to matter more generally useful and indispen- 
sable. Those selected, however, are treated with all necessary 
fulness and perspicuity, and will be found all that are required 
for actual work. For the same reason, some of the methods de- 
scribed in my Practical Treatise diVQ left out. Among those which 
are now omitted, is the isochronous stud, that not being in prac- 
tical use, because it does not allow the use of a regulator with 
it. Some ten years ago, I patented a very simple modification 
of this method, removing that objection, but, owing to certain 
provisions of the patent law, the patent became void, and I let 
the matter drop. It is now free to any who choose to use it. — 
The methods to be described are: 

(560.) 1. Isochronizing by a certain length. — Springs will only 
secure isochronism within certain limits. With the fiat spiral, 
it can be isochronous if the vibrations do not exceed i^ turns. 
When provided with terminal curves, as in the case of the 
Breguet and cylindrical springs, the vibrations may be isochro- 
nal up to \\ turns, or a little over that. A spring which is too 
short, i.e.^ too thick in proportion to its length, will gain in the 
short vibrations and lose in the long ones, and vice versa. The 
shorter the spring, the greater the difference of rate in the long 
and short arcs; and the longer it is, the less the difference, and 
the less necessary is it to pin it in any particular way. Hence 
flat spirals and Breguet springs which employ regulators should 
be long, so that the change of length by the regulator may pro- 
di>ce the least difference between the rates in the long and short 
arcs. The length of the flat spiral (for lever watches) should 
be at least 14 coils, and for the Breguet spring from 14 to 20 



THE WATCH ADJUSTER'S MANUAL. 233 

coils. In cheap watches, use shorter springs, to quicken the 
short arcs. Cylindrical springs run from 10 to 13 turns. 

(561.) Alloivance for adjustment or nofi-adjusttnent. — When 
springs are to be closely adjusted, they may be shorter, as, in 
short springs, differences in the mode of pinning, in the length, 
and other influences, produce a greater effect on the rate in 
different arcs, and consequently we can isochronize a short 
spring through a wider range, and counteract greater position 
and other errors by the adjustment than could be done with a 
long spring. Long springs are therefore better in watches 
which are not to be adjusted, or not adjusted closely, because 
the difference of rate in the long and short arcs is less. But for 
that reason they cannot correct very large position errors, and 
when such errors are large a shorter spring of the same strength 
is preferable. In substituting or fitting springs follow the above 
indications. In altering a spring, shorten it to make the short 
arcs faster, and lengthen it to make the short arcs slower. See 
section (630). 

(562.) It is also necessary to correct the rate of the watch, 
which will be altered by thus shortening or lengthening the 
spring. If the long arcs are only a few seconds slow, take up 
the spring half the width of the stud, then make the balance 
heavier to neutralize the effect on the rate, as by putting two 
heavy screws in place of two light ones; if the long arcs are too 
quick, let out the spring and make the balance lighter to corre- 
spond. The necessity of making two changes renders this 
method rather troublesome. But the same objection lies against 
nearly all of the methods except that by terminal curves. 

(563.) 2. By takifig up and letting out the spring. — As the re- 
verse of the foregoing method, we have the well-known rule 
among adjusters: "If taking up the spring don't accelerate the 
short arcs, let it out some." This might be explained on the 
theory that there is an isochronal point in every coil, and that 
lengthening the spring would carry the end further away from 
the isochronal point in one coil, while bringing it closer to that 
in another, but not near enough to be appreciably benefited by 
it. The change of length may be beneficial or otherwise, ac- 
cording to which isochronal point is nearest. This method is, 
roughly speaking, merely "feeling around" to find the isochro- 
nal point. To prevent the spring being damaged by frequent 
pinnings in the stud, one of the tools described in Chapter XVII 
will be found invaluable, as it grips the spring between flat 
jaws and produces no crimp or injury, no matter how many 
times the place of holding it is changed. It is not even neces- 



234 THE WATCH ADJUSTER'S MA.VUAL. 

sary to remove the stud for the trials, (in the case of watches,) 
as the coil can be gripped on either side of the stud, which will 
swing with it and do no harm if it is not too heavy, and if the 
watch is kept in the horizontal position during the trials. 

(564.) 3, By pinning the spring in even turns. — This method 
was at one time thought to be a cure-all for isochronal errors, 
and all springs were thought to be made isochronous by merely 
avoiding fractional parts of coils. That is now known to be an 
error, but that method of pinning has certain advantages which 
are important. One of them is that the difference of rate be- 
tween long and short arcs is least with even turns, while it is 
greatest with half turns, and proportionally great as we change 
from even coils to the half coil over or under the complete turns. 
Hence, for watches which are not to be adjusted, complete coils 
will generally secure vibrations with the least isochronal errors. 

(565.) Principle of the isochronal adjustmetit by even turns. — 
But if the spring is to be adjusted for isochronism, it can be 
made to cover greater errors (of positions, frictions, etc.,) by 
pinning it over or under complete coils. For instance, if there 
was a large loss in the short arcs, due to various disturbing 
influences, and we could produce an equally large gain in the 
short arcs due to isochronal error, we should obtain a perfect 
rate, and the spring would be called isochronous. The isochro- 
nal error might be insufficient for the purpose, if pinned in even 
turns, but it could be made greater by properly changing the 
spring in the stud, till the necessary amount is obtained for 
counteracting the effects of friction, etc. The error produced by 
pinning over or under even turns becomes greater as the spring 
gets shorter. If the isochronal error in the short arcs is a loss, 
the loss will (as a general rule) be greatest when the spring is 
pinned in half turns, other conditions being the same. If the 
isochronal error is a gain, the gain will be greatest when pinned 
in half turns. 

(566.) This method consists, of course, in bringing the two 
ends of the spring, or ^'points d" attache^'" as they are termed, 
in the same radius, i.e.^ a line drawn from center to outside 
passes through both the end at the collet and that at the stud. 
But we find in practice that with any given hair spring, the 
isochronal point would require to be at different places in it, 
depending upon the construction of the balance, the escape- 
ment, etc., — even changing the size of the coils will cause the 
isochronal point to vary its position. The most that any 
method can do is to enable us to approximate to the isochronal 
point, leaving the corrections to be done by means of testing 



THE WATCH ADJUSTER'S MANUAL. 235 

and adjusting. And, although I have examined a great many 
fine-running watches for that purpose, I have not yet found one 
where the spring was pinned exactly according to this theory, — 
the nearest always being a little to one side or the other. Nor 
have I succeeded in closely isochronizing a spring according to 
this theory, without resorting to the regulator pins (585) to 
enable me to complete the adjustment without changing the 
points (T attach^ of the springs. But as this mode of pinning 
enables the workman to fit his spring with tolerable accuracy 
attended with scarcely any extra labor, it should be generally 
followed, even when the spring is not intended to be isochro- 
nized, as I have already recommended. Even a low-priced job 
should always be done as well as can be afforded. This method 
will at least guide us to an eligible starting point, at or near 
which we may reasonably expect the spring to be isochronal. 
It should be observed that if the regulator is not very near to 
the stud, that is to say, within 20° to 25° from it, the whole 
coils are reckoned from the point touching the collet to the 
regulator pins ^ instead of to the stud. If the isochronal point is 
not at the even turn, or if the spring is not pinned in even turns, 
changing the pinning towards even turns will generally make 
the long vibrations quicker. Further remarks on this subject 
will be found in Part Fifth on Rating. 

(567.) 4. By fractional coils. — As before stated, (561,) the 
error of rate increases as the pinning is changed from even turns 
to half turns, and in adjusting we increase the variation from 
even turns till the isochronal error balances the opposite error 
of positions, etc. Of course, we produce a loss to balance a 
gain, and vice versa., making the spring shorter to cause a gain 
in the short arcs, and longer to make them slower. As a rule, 
pinning in half turns snakes the long vibratiojzs slower. But in 
watches with frictional escapements, short springs and short 
arcs, such as the duplex and cylinder escapement, the least 
observable error is found, (i.e.., the isochronal error most nearly 
balances the frictional errors, etc.,) when the springs are 
pinned nearly half a turn short of complete coils. In box chro- 
nometers, the result is best when the (cylindrical) springs are 
pinned about a quarter of a turn short, but in pocket chronome- 
ters they are pinned in even turns. Breguet springs are gener- 
ally pinned in even turns if not adjusted for isochronism. When 
adjusted, they follow the same rule as all others. Also, see 
Isochronizing by terminal curves, {589 to 610.) 

(S^^-) 5- ^y (ilterifig the frictions. — As a general rule, friction 
makes the short arcs slower. It, of course, retards both long 



236 THE WATCH ADJUSTER'S MANUAL. 

and short arcs, but being proportionally greater in the short 
arcs, it retards them more than the long ones. This includes 
friction arising from rough or poorly polished jewels, pivots 
imperfect, jewel holes too long, etc. Improving these con- 
ditions will of course make the short arcs quicker, or make the 
loss less. Thickening of oil on the balance pivots, dirt, etc., 
make the short arcs slower. But if the thickening of the oil is 
on the pivots of the escapement or train, it makes the short arcs 
faster. See section (573). The short arcs can be made quicker 
in either horizontal or vertical positions by lessening the friction 
in those positions, and slower by increasing the friction. 

(569.) 6. By altering the balance pivots. — When the watch is 
held in the vertical position, the side friction on the balance 
pivots makes the short arcs slower, in proportion to the amount 
of the friction and the size of the pivots. Hence shortening 
the holes, and polishing them, will quicken the short arcs. 
When the pivots are too closely fitted in the holes, the friction 
retards the short arcs, and any variation in the consistency of 
the oil produces considerable effect on the rate. Slightly 
freeing the pivots by hard burnishing will considerably quicken 
the short arcs. When the balance pivots are rather large the 
friction increases very rapidly, and reducing the size of the 
pivots (and of course fitting smaller jewel holes,) will greatly 
quicken the short arcs. This fault is very noticeable in small 
watches where the size of the pivots is large in proportion to the 
size of the balance, and in such cases the short arcs are quick- 
ened by using a hair spring one or two coils shorter. This 
alteration of course quickens all the vibrations, but the short 
ones more than the long. 

(570-) 7- -^y ^^^^ balance. — The isochronism can also be altered 
by changing the size or weight of the balance, but the results 
are so uncertain that the method is not followed by adjusters. 
See Chapter XXXVII, section (697.) In marine chronometers 
the long arcs are slow, which is attributed to the rims flying 
outward by centrifugal force further than in the short arcs. This 
error is greater when the rims are thin and narrow, than when 
wider and thicker. It has been proposed to make the long arcs 
slow in watches having expansion balances, by drilling a hole 
through each segment, near the ends of the center bar, and en- 
larging these holes, and thus weakening the segments, till they 
would fly out in the long arcs sufficiently to make them as slow 
as required. But this method cannot be considered commend- 
able. 

(571.) 8. By altering the escapement frictions. — In the duplex 



THE WA TCH ADJUSTER'S MANUAL. 237 

and cylinder escapements we may vary the isochronism by vary- 
ing the relative amounts of the escapement-friction and the arcs 
of vibration. For instance, if the escapement be changed so as 
to transmit the motive force more advantageously and increase 
the impulse-power, without changing the friction upon the roller 
or cylinder, the arc of vibration will be increased and the long 
arcs will be slower than the short ones. (So in general, any 
alteration which increases the arcs without changing the escape- 
ment-friction, will make the long arcs slower than the short 
ones.) But increasing the friction without increasing the im- 
pulse-power, will make the long arcs quicker. So in general, 
any change which lessens the effective impulse-power, without 
lessening the escapement-friction, will make the long arcs quicker 
than the short ones. 

(572-) 9- By altering the drops. — In the chronometer and 
duplex, the short arcs may be made slower by making the lock- 
ing spring stiffer, or by giving the escape wheel more drop upon 
the impulse pallet, both of which operations are highly objec- 
tionable. But these methods are of no great practical impor- 
tance, because it is, of course, not advisable to make the 
escapement worse off in order to improve the isochronism; and 
on the other hand, the escapement should be in as good order as 
we can get it, before we undertake to isochronize the spring. 
So there is very little margin left for our alterations. 

(573-) lo- ^y (^li^fif^g the motive force. — As a general rule, 
stronger motive force makes the short arcs faster; (see section 
(571;) and diminishing it makes them slower, because the fric- 
tions, etc., are more felt. But this should be done with great 
caution, for there is a correct proportion between the motive 
force of the mainspring and the weight and diameter of the bal- 
ance, which should not be greatly departed from. When the 
vibrations are very large, in the lever or chronometer, it is 
allowable to lessen the force of the mainspring, or put in a 
weaker one, to make the short arcs slower; and the reverse of 
this may be done to make the short arcs faster, if the vibrations 
are rather short, and can be safely enlarged. But the above 
remarks will show how incorrect is the idea that isochronism 
can depend upon the hair spring alone. 

(574.) II. By changing the distance between the coils of the hair 
spring. — It has been found that the difference of rate between 
long and short arcs is least when the distance between the coils 
of the flat spiral is equal, and greatest when that distance is 
most unequal. If the distance is the same at the center of the 
spring as at the outside, there will be the least difference in the 



238 THE WATCH ADJUSTER'S MANUAL. 

long and short arcs. If the distance between the coils increases 
from the center to the outside, the difference between the long 
and short arcs increases. When the springs are fire-hardened and 
tempered in the same form as they are wound, the distance is 
practically equal. Such springs are best for watches which are 
not adjusted for isochronism, as their isochronal errors are 
small. But in adjusted watches, the distance between coils 
should vary, in order that there may be a greater difference of 
rate in the long and short arcs, so that the isochronal adjust- 
ment may be able to correct larger positional and other errors, 
and secure a more perfect rate. The method by which such 
springs may be made is given in Chapter VIII. The adjustment 
is accomplished by changing the place of pinning until all errors 
are covered by the isochronal action of the spring. See sec- 
tions (564) to (567,) also Chapter XXXIV. 

{575.) 12. By exce7itric spring, — Mr. Kullberg is the princi- 
pal exponent of this method, which is largely followed, and 
I give his explanation of the principles involved. He utilizes 
the normal excentric action of the flat spiral spring while vibrat- 
ing, which always occurs, even when it is so formed and pinned 
in the stud that its coils are concentric with the balance axis 
when at rest. As the balance vibrates in such a direction that 
the coils open, they open most on the side distant from the stud, 
because it has freedom on that side, but on the side next to the 
stud it is prevented from expanding freely. The result is that 
all the coils become excentric, and more so in proportion as the 
vibrations are larger. When the balance vibrates in the oppo- 
site direction, the result is the reverse of that described, and 
the spring is excentric on the side next to the stud. It is con- 
centric only when the balance passes the point of rest, the pres- 
sure being alternately against one side of the jewel holes and 
the other, causing the usual error of the flat spiral — the long 
vibrations too quick and the short ones too slow. 

(576.) He remedies this by forming and pinning the spring 
so that it is excentric when at rest, Z.^-., it "bulges" towards the 
stud. When the spring uncoils in vibrating, it expands most 
on the side opposite the stud, as before. At a certain point in 
the vibration the coils become concentric with the balance axis, 
but if the vibrations become still larger, the coils again become 
excentric, but on the opposite side. In each vibration, there- 
fore, the center of the excentricity travels from side to side, 
past the balance axis, as before, but the center of the coils 
comes on the axis at a different time — not when the balance is 
at the point of rest. 



THE WATCH ADJUSTER' S MANUAL. 239 

(577.) That time can be varied, to produce the effect required 
for correcting the error of isochronism. The spring is usually 
caused to be concentric when the balance has passed through 
half the distance it usually vibrates, (being held in that position 
while the coils are bent into concentric position,) but if neces- 
sary they can be made concentric at or near the end of the 
vibration. The spring is thus tried and changed till the proper 
action is obtained. The increased arc of vibration is an indica- 
tion of a change for the better. The benefit is partly due to 
equalizing the frictions on the pivots. With the flat spiral there 
will unavoidably be some side pressure on the pivots, and the 
shiftings of the spring are to equalize them and neutralize the 
friction errors. This is the usual explanation of the method, 
but another and better one is given in sections ((^ZZ-) 634> 660). 

(578.) This procedure is only recommended for making the 
short vibrations quicker and the long ones slower. It is claimed 
that in this way the flat spiral can be made as isochronous as 
the Breguet or cylindrical spring. Nevertheless, it is a method 
which cannot be considered advisable or workmanlike, and is 
only excusable because it does not produce excentricity when it 
did not exist before, but only shifts the existing excentricity to 
different points in the vibration, to reduce its injurious effects 
on the isochronism. Independent of any adjustment, it is quite 
common to pin the flat spiral excentric towards the stud, both to 
lessen the extreme of excentricity and to quicken the short arcs, 
as a remedy for the retarding effects of the oil in cold, of the 
dirt, etc. For lever clocks, and the like, it would be useful for 
making them keep the same rate when 
wound up or partly run down, especially 
those running longer than one day. 

(579-) ^3- ^y regulator^ on Breguet 
over coil. — There is no more propriety in 
using a regulator on a Breguet spring 
for timing purposes than on the ter- 
minal curve of a cylindrical spring. 
The Breguet overcoil is as truly a ter- 
minal curve as the other. Manufac- 
turers and others will sometimes form Fig. 31. 
a part of the overcoil into a good ter- 
minal curve, and another part in a concentric arC; with the ap- 
parent belief that the terminal will perform its functions in 
substantially the same way, notwithstanding the presence of 
the concentric arc. How erroneous that idea is will be seen 
in Fig. 31. Let us suppose that the curve c c'd from c to d 




240 THE WATCH ADJUSTER'S MANUAL. 

(half a turn in length) is what the spring really requires to 
make it isochronous. To one end of it is joined the concen- 
tric arc e d for the regulator, and to the other is added the 
portion c 3, to avoid too great abruptness. The overcoil then 
has the form be c' de, and it is a true terminal curve having that 
shape. It is perfectly clear that the portion c c' ^will not act as 
it would if it alone connected the point b with the stud at e, 
because it is merely ^/<2r/ of the curve be; and it is equally 
clear that the curve bce'de cannot possibly be made to have the 
same action as ^^V would have alone. Of course, no springs 
are made in the form drawn; but it serves to show that, no 
matter how correct the form of the curve may be, it loses its 
value when a concentric arc is added, apart from the changes of 
length produced by the regulator. The directions for regulat- 
ing a Breguet spring with concentric arc given in Chapter XXII 
refer to such a spring, i.e.^ to a eombination of a terminal curve 
and a concentric arc, as they are usually made. 

(580.) A better form. — A better form, if a regulator must be 
used on it for timing purposes, would be obtained by making a 
gradual curve, (as shown in dotted lines,) from the end of the 
concentric arc at d to the spring at b\ Fig. 31 ; or, if a full turn 
is wanted, make the curve in the form dc"cb. The center of 
the regulator would then be at a^ the center of the spring, and 
it would have a concentric arc de., of 90°, to act upon, while the 
whole length, from e \,o b (or to ^') should be formed to act as 
a terminal curve. The shifting of the regulator will, of course, 
change the acting length of the curve, and in order that this 
shifting may affect the isochronism as little as possible, such 
springs should be very long, (560,) should be equally open from 
center to outside, (574,) and should be pinned in even turns. 
The overcoil should also be as regular in form and as long as 
allowable, so that the shifting of the regulator may change its 
total length and shape but slightly. 

(581.) The best for77i. — The concentric arc so made is always 
more or less objectionable, as not fully meeting the require- 
ments of a terminal curve. I believe I was the first to point 
out a way to overcome this objection, in the first edition of The 
Practical Treatise^ which is to abandon the co?nbination (579) and 
use only the terminal curve. Form the overcoil into a regular 
terminal curve, as in Fig. 32, having the portion de formed as 
the arc of a circle, whose center is not at a, the center of posi- 
tion of the spring, but at «', which may be located wherever 
the general form of the curve brings it. Then plant the regu- 
lator center at a' . It would have a sweep of 90° on the spring, 




THE WATCH ADJUSTER'S MANUAL, 241 

without necessarily injuring the form of the q,\xxv^ dc b. To 
lessen its effect on the isochronism, the spring should conform 
to the same conditions as named in section (580.) As regards 
pinning in even turns, it should be pinned 
at that or any other point which was found 
to be least sensitive, ?>. , where the iso- 
chronal errors caused by moving the reg- 
ulator would be smallest. The number of 
coils should also be that which would 
make the spring least sensitive. Manu- 
facturers could easily ascertain the most 
desirable arrangement, and adopt it. But 
this improvement can also be practised 
by adjusters, and even by ordinary watch- Fig. 32. 

makers. 

(582.) Isochronizing by regulator^ on te?'f?nnal curves. — The prin- 
cipal object of the foregoing details about timing by the regu- 
lator is to make clear the method of isochronizing by means of 
a regulator, when it is used for adjusUnent^ instead of for rating. 
In that case, the requirements mentioned in the preceding sec- 
tions would be reversed, and the number of coils, mode of pin- 
ning, and length of overcoil should be such as would cause the 
errors produced by shifting the regulator to be as great as possi- 
ble^ (580,) since a less shifting would then produce the required 
effect. The coils should become more open, the distance be- 
tween the coils being about twice as great at the outside as at 
the center. The regulator pins should be as close as possible 
without binding on the spring, and they should be kept near the 
stud, to prevent the reverse action of the coil between the pins 
and the stud. 

(583.) If these conditions are complied with, the adjustment 
will be facilitated by the use of the concentric arc, because the 
shifting of the regulator would be substantially equivalent to 
taking up or letting out the curve in the stud, without displac- 
ing the balance, or requiring the beat to be corrected and the 
remainder of the curve reformed. But in a fine watch, that 
should be done in the stud. When the adjustment is finished 
the rate will, of course, require to be corrected by the balance 
screws, as in this case the regulator is not available for timing 
purposes. It should be remembered that shifting the regulator 
always affects the isochronism, even when it is done for timing 
purposes. Hence it should be kept as near as possible to the 
stud, as, when it is far from the stud, even close timing by it is 
impossible. 
16 



242 THE WATCH ADJUSTER'S MANUAL. 

(584.) 14. By regulator on flat spiral sprmg. — The use of the 
regulator for isochronizing is seldom advisable, but when it is 
resorted to, the requirements are the same as described in sec- 
tion (582) for the Breguet spring, except those relating to the 
overcoil. The length, openness of coils, mode of pinning, 
form and position of regulator pins should be as there directed, 
and the rate should be corrected by the balance. Further in- 
structions are hardly necessary. 

(585.) 15. By ope?itng or closing regulator pins. — Another 
method is by opening or closing together the pins of the regu- 
lator, and is an attempt to secure the same results of changing 
the stiffness of the hair spring as are secured by terminal 
curves. It is mainly applicable to the ordinary fiat spiral 
springs. In this method the stiffening of the spring is effected 
by its contact with its pins; the action of the spring, before stif- 
fening, takes place while it remains free between the pins, and 
is virtually without any control entirely up to the stud. The 
idea is that the longer it remains free the slower the vibrations 
will be, while the earlier in the vibration the pins come into 
contact with the spring and stiffen it, the quicker the vibration 
will be. Of course, this effect is produced in both the long 
and short vibrations, but it is greater in the latter, because the 
difference produced by opening or closing the pins is in a greater 
proportion to a short arc than to a long one. Hence, if the 
watch loses in the short vibrations, it shows that the stiffening 
of the spring does not commence early enough, consequently the 
regulator pins are too wide and must be brought closer together. 
If it gains in the short vibrations, it begins to stiffen too soon 
and completes the vibrations too quickly. The pins must there- 
fore be opened a little, which increases the length of the slow 
part of the vibration before the spring comes against the pins, 
and shortens that part of it in which it is stiffened and hurried 
up by the contact with the pins. 

(586.) At first thought, this appears to be all that could be 
desired, being easy, quickly done, and apparently meets all the 
conditions of isochronism. But the objection is that the regu- 
lator has its own office to perform in the mechanism of the 
watch, and for its perfect performance it must be made in a cer- 
tain manner. Among other things, the pins should be as closely 
together as possible, while avoiding any binding upon the spring 
when its position is shifted. Therefore we should not permit 
any material departure from the form which will best preserve 
its true functional character, for the sake of accomplishing 
some other end. But this method is well adapted for all 



THE WATCH ADJUSTER' S MANUAL. 243 

classes of fine clocks, both American and imported, and whether 
having lever or cylinder escapements. For watches it is not 
well adapted, except those in which there are but few coils of 
the hair spring and they are wide apart, to which more room is 
usually given in the regulator, as will be noticed in a large 
share of English lever and duplex watches. 

(587.) The cylinder escapement watches may also be advan- 
tageously isochronized in this way, as their low price generally 
precludes the employment of the more expensive methods. And 
it must be admitted that a well-made cylinder or duplex watch, 
particularly when provided with the fusee and chain, may be 
adjusted very closely by this method. For this purpose the 
regulator pins are placed further apart than stated in (586), 
when fitting the spring, so as to allow of either opening or clos- 
ing them a little, as might be required by the adjustment. 

(588.) But in fine watches, its use, if allowed, at all, should 
be restricted to the finishing touches, which would require only 
the very slightest alterations of the pins, which, in this case, 
I should advise to be placed at the proper distance apart at the 
start, and only change them by opening them very slightly. 
Should a still wider opening be required, or if it proved neces- 
sary to bring the pins a little closer together, (which, of course, 
could not be done,) the hair spring should be moved in the stud, 
according to section (561). In all cases, when the adjustment 
is completed the two pins should be left parallel, not inclining 
toward each other, so that, if the spring should play between 
them at a higher or lower level, it would still find the same 
width of opening. Some workmen make the short arcs faster 
by causing the hair spring to press more or less against the reg- 
ulator. But this practice is entirely wrong. 



CHAPTER XXXII. 

ISOCHRONIZING BY TERMINAL CURVES. 

(589.) 16. By terminal curves on the spring. — The method most 
approved is by curving one or both ends of the spring towards 
the center, pinning them at half the radius, i.e.^ at half the dis- 
tance from the center to the outside of the spring, and giving 
the curved portion such a length and form as will cause the 
spring to gain or lose the proper amount for securing isochronal 
vibrations. (557.) When this method is practiced with the flat 
spiral spring the curved portion is called the Breguet overcoil, 
it being raised so that it can curve toward, the center over the 



244 THE WATCH ADJUSTER' S MANUAL. 

Other coils. Theovercoil is generally rather long, varying from 
f to i^ turns. Springs with overcoils are usually called Breguet 
springs. The cylindrical spring has both ends curved toward 
the center as above described, and these curved portions are 
called terminal curves. They vary in length from a full turn, 
in pocket chronometers, down to less than a half turn in marine 
chronometers. There is no particular form which has any ad- 
vantage over others, but both reasoning and experience indicate 
that it is advisable to have the form as regular, or free from 
abrupt changes of direction, as possible, because it is more 
easily changed for adjusting purposes, and a change of length 
or shape necessitates less labor in making the rest of the curve 
or spring conform to it. 

(590.) The general fu7ictions or effects of a terminal curve are 
(i) to make that portion of the spring either more or less rigid 
than the adjacent portions, as a short or abrupt curvature offers 
more resistance to bending than a larger or more gradual curve, 
and vice versa. It thus produces a difference of action between 
the long and short arcs, without changing the rate at the arc 
of medium extent — the true " rate" of the watch depending 
only on the length of spring in action. (2) To enable the spring 
to expand and contract more freely and equally in all direc- 
tions, without displacing the body of the spring and causing 
side pressure on the pivots. (3) To change the point of greatest 
strain to a greater or less distance from the end, as may be re- 
quired to secure isochronal vibrations. In other words, to vir- 
tually translate the acting end of the spring from point to point, 
at different periods during the vibration. 

(591.) The virtual end of the spring. — In any spring, when it 
begins to bend as the balance leaves its central position or point 

of rest, it will bend most where the spring 
is least curved, and will bend least where 
the curves or coils are the smallest and 
most rigid. 

In the case of a cylindrical spring, where 
all parts have an equal curvature, if one 
end is fastened to the stud and the other to 
the collet, exactly in the outer circle, the 
whole of the spring will bend equally. But 
FigT^S. ^^ ^^^ collet end, for instance, is formed 

into a rigid curve e b, Fig. 2)Z^ ^o^, say, 
half an inch, that curve will not bend appreciably until some 
other portion of the spring has been bent sufhcientl)' to make its 
resistance equal to that of the curve. 




THE WATCH ADJUSTER'S MANUAL, 245 

(592.) At the beginning of the vibration or " excursion" of 
the balance, therefore, the collet end of the spring would virtu- 
ally be at one end of that curve, at b, instead of at the collet ^, 
i.e.^ the vi-tual length of the spring would be half an inch less 
than the actual length. If this curve was rigid enough to escape 
bending at all during the short arcs of vibration, they would be 
very much quickened, for the spring would virtually be half an 
inch shorter during the short vibrations than in the long ones. 
If each end of the spring had such a curve as described, the 
virtual ends of the spring would be half an inch from both collet 
and stud, and its virtual length during the short vibrations 
would be an inch less than during the long ones, causing a great 
difference of rate between the long and short arcs. 

(593-) T^ make the short vibrations either quicker or slower. — 
As a matter of fact, however, the curves do bend a little, even 
at the beginning of the vibration, and do 
so more and more as the amplitude of the 
vibration increases. This greatly reduces 
the effect of the curve, but the princVle 
still holds good, and it explains how a ter- 
minal curve can make the short arcs quicker 
than the long ones, when the actual length 
of the spring is the same in both cases. 
In the foregoing instance, the curve is more 
rigid than the remainder of the spring, and Fig~T4 

virtually makes it shorter, during the short 
arcs. But if we make the curve less rigid than the remainder 
during the short arcs, the spring will virtually be longer, and 
will lose, during the short vibrations. In Fig, 34 I have shown 
such a curve, e b^ which would not become as much curved and 
rigid as the body of the spring till in the last half of the vibra- 
tion, and therefore would make the long vibrations much quicker 
than the short ones. 

(594.) The proper form for ter77iinal ctirves. — In any terminal 
curve, that part which is more curved and therefore more rigid 
than the body of the spring tends to quicken the short arcs, 
and the portion which is less rigid makes the short arcs slower 
and the long arcs quicker. This emphasizes what I said con- 
cerning the propriety of making a curve regular in form, because 
if one part is more and another part less rigid than the remainder 
of the spring, the two parts neutralize each other, and the only 
virtue of the terminal arises from the excess of one part over the 
other. Hence the fallacy of such curves as that of Phillips, in 
Fig. 27, where the part db neutralizes the part e d, and renders 




246 THE WATCH ADJUSTER'S MANUAL. 

it difficult to tell without trial whether it would make the short 
arcs quicker or not. When a terminal curve is properly formed, 
its action can be ascertained by inspection, without trial; if its 
form does not indicate whether it will make the short arcs 
faster or the long ones, trial will show that it has but little 
effect either way. 

(595.) Form a7id length of terminal curve. — The greater the 
curvature of the terminal, the longer it continues to act as de- 
scribed, because the balance will be nearer the end of its excur- 
sion when the remainder of the spring becomes equally rigid and 
brings the terminal into equal action with it. If the curvature 
of the terminal is greatest at the stud, (or the collet,) and be- 
comes less and less rigid from there to its end or junction, the 
virtual end of the spring will be at the junction of the spring 
with the terminal, when the balance excursion begins; but as 
the body of the spring becomes more and more curved, and its 
rigidity thus becomes equal to that of a constantly increasing 
portion of the terminal, the virtual end of the spring will travel 
along the terminal, from the junction to the stud. The specific 
action of a terminal increases as its length becomes greater. 
When the above conditions are reversed, the actions and results 
will of course be the reverse of those stated. 

(596.) Meanifig of ter7?is used. — In speaking of the beginning 
and end of the excursion or vibration in this explanation of the 
action of terminal curves, I refer to the flexion of the spring, 
from the point of rest of the balance to the end of its arc, i.e., 
I refer to one-half of what is usually called " the vibration," and 
to that half during which the spring is wound up and becomes 
more and more rigid. The beginning is at the point of rest, 
and the end is the limit of its movement. During the other 
half, in which the spring uncoils or opens, it of course becomes 
less curved and therefore less rigid, and the action is the reverse 
of that stated. But for the purpose of explaining the action 
of terminals, it is only necessary to describe the coiling up of 
the spring, as the reader can readily see what the action must 
be in the other half of the vibration. The beginning or end of 
the terminal refers to the point at the stud or collet, and the 
"junction" is the point where it meets the body of the spring. 
I call a terminal which is more curved and therefore more rigid 
than the adjacent body of the spring a plus ter7ninal, because it 
makes the short arcs quicker. A terminal which is less curved 
or less rigid than the body of the spring I call a inimis termi7ial, 
because it makes the short arcs slower. A terminal which con- 
tains curves or portions of both characters is a mixed terminal 
or mixed curve. 



THE WATCH ADJUSTER'S MANUAL. 247 

(597.) Mixed terminal curves are those which have portions 
producing contrary effects, i.e.^ one portion may be more and 
another less rigid than the rest of the spring. As before stated, 
the effect of such a terminal is due to the excess of one kind 
over the other. In some cases mixture cannot well be avoided. 
For instance, Fig. 34 is drawn to illustrate a curve less rigid 
than the body of the spring, and which would make the short 
arcs slower and the long arcs quicker. But if a curve was 
actually made as shown, it would evidently cause displacement 
of the spring and side pressure during the vibration, and to 
avoid this it would be necessary to introduce a portion with more 
curvature, to connect the point b with the body of the spring. 
Another curve at e would also improve it. The curve shown in 
Fig. ZZ would also require to be tested as regards side pressure, 
and in fact that should be done with every kind of terminal. 
In making mixed terminals, the different parts should not be 
nearly balanced, but the portion which produces the desired 
effect should constitute the major part of the curve, and only 
enough of the opposite character introduced to prevent side 
pressure, etc. A good illustration of the employment of mixed 
terminals will be found in Fig. 37, (617,) which represents the 
spring and both terminals of a marine chronometer. A poor 
example is the Breguet curve in Fig. 36, (604) in which from e 
to / is minus, from / to ^is plus, and from ^nearly to b is minus. 

(598.) Action of plus terminal curves. — It may be well to again 
explain that although the whole of the spring (see Fig, 2ii) does 
bend, from the beginning of the vibration, the terminal curve 
bends less than the body of the spring, being more rigid. Its 
action is the same as if the terminal had retained the original 
curvature of the body of the spring, but had been shortened 
sufficiently to bring it to the same rigidity. This virtual short- 
ening is greatest at the beginning of the balance excursion. As 
the spring becomes wound and bent into smaller circles, it be- 
comes more rigid, there is less difference in that respect between 
it and the terminal, the latter bends proportionately more than 
before, its virtual shortening is less, and the spring becomes 
virtually longer. This change in their relative conditions goes 
on till the end of the excursion, and the virtual end of the 
spring constantly comes nearer to the actual end. When the 
body of the spring acquires a rigidity equal to that of the curve, 
both will bend equally, and the virtual and actual lengths of 
the spring will be equal. 

(599.) Action of minus terminal curves. — When the terminal is 
less rigid than the adjacent body of the spring, its action is 



248 THE WATCH ADJUSTER' S MANUAL. 

the same as if it had retained the original curvature of the 
spring but had been lengthened \.o bring it to the same rigidity as 
it possesses in the terminal. That is to say, it is equivalent to 
lengthening the spring while leaving it in its original form. 
This virtual lengthening is greatest at the beginning of the ex- 
cursion, and the terminal then bends more, in proportion to its 
length, than the body of the spring. As the balance moves fur- 
ther from the point of rest, both the terminal and the body of the 
spring become more rigid, but the terminal does so more rap- 
idly than the other part, the difference of rigidity becomes con- 
stantly less, and the virtual lengthening of the spring decreases, 
/. ^. , the spring virtually becomes shorter and shorter, until their 
respective rigidities are equal, when they will bend equally and 
the virtual length of the spring will be the same as the actual 
length. The shortest vibrations will therefore be slowest, be- 
cause the virtual length of the spring is then greatest, and the 
long vibrations will of course be quicker than the short ones. 

(600.) The meaning of gain or loss in the short arcs. — With a 
plus terminal the short arcs will therefore be quicker than the 
medium, and the medium arcs quicker than the long ones. If 
we take the long arcs as the standard, we shall say that the 
short arcs gain; if the short arcs are the standard, we will say 
that the long ones are slow; if the medium arcs are the stand- 
ard, then we must say that the short arcs gain and the long 
ones lose, but the gain and loss are only half as much as in the 
two previous cases, because we now compare each end with the 
middle of the scale, instead of with the other extreme. It is 
almost universally customary to take one of the extremes as the 
standard, because it is so easy to get the long arcs by placing 
the watch in the horizontal position, and the short ones in the 
hanging or vertical position; but it is not so easy to get the 
medium arcs, although that is the proper way to find the true 
rate of the spring as due to its actual length. 

(601.) Meaning of 710 loss nor gain in the short arcs. — This gain 
or loss is the actual performance of the spring. When run in 
the watch, however, the rate observed does not depend on the 
spring alone, but also on the frictions and other influences af- 
fecting the motion of the balance. If, with such a spring as that 
shown in Fig. 2,2,, and taking the rate in the long arcs as the 
standard, we should find that the rate was the same in the short 
arcs, most workmen would say that the spring was isochronous 
and its action was precisely the same in both long and short 
arcs. But that would be a great mistake. We all know that 
friction and the like greatly affect the rate, and that such effect 



THE WATCH ADJUSTER'S MANUAL. 249 

is unavoidable. Let us suppose that their effect in this case 
was to cause a loss of 8 seconds in the short arcs. Reason 
would tell us, if we found no such loss, that the spring must 
have been in a condition to gain 8 seconds, and that that gain 
had just balanced the loss due to frictions, etc. It is true that 
the spring would be isochronous; but it would be so, not be- 
cause its action had been the same in the long and short arcs, 
but because it had 7iot been the same. If it had, it would not 
have corrected that error, and the watch would still have lost 8 
seconds in the short arcs. 

(602.) Adjusting by alter i?ig the length of terniinal airves. — In 
adjusting, /.<?., in altering the curves to produce certain desired 
effects, we may change either their length, 
their form, or both. If we adjust plus ter- 
minals by their length, we make them longer 
to quicken the short vibrations, and shorter 
to make them slower. Fig. 35 is the dia- 
gram used from time immemorial to illus- 
trate the alteration of terminals. If the 
terminal has the form ^, for example, and 
the watch gains in the short vibrations, we 
make the terminal shorter, and bend a por- y\q i,c. 

tion of it back into the form of the outer 

coil, as shown by B, which is considerably shorter than A. On 
the other hand, if there is a loss in the short vibrations, we 
quicken them by making the terminal longer, as shown at C, by 
taking more of the outer coil into the terminal. 

(603.) The philosophy of the change is plain. The longer the 
plus terminal is, the further the virtual end of the spring is from 
the stud (or collet) e, i.e.^ the more of the spring is virtually cut 
out, at the beginning of the vibration; and the shorter the ter- 
minal is, the greater is the virtual length of the spring, at the 
commencement of the vibration. As examples, Fig. 33 shows 
a short curve, which could be made longer like edb' in Fig. 31, 
or still longer like edcbm Fig. 32, which is fturn; or like 
edc"cb in Fig. 31, for a full turn, and each such change would 
make the short arcs quicker. If we want to make them slower, 
along terminal can be shortened upas required. Adjusting by 
altering the length is the easiest, most rapid and most certain 
method. 

(604.) Adjusting by altering the for 771 of the terminal curve. — If 
we adjust by changing the form of the terminal, the general 
principle to be followed (with a plus terminal) is, to make the 
curvature more gradual, i.e.^ flatter, to quicken the long vibra- 





250 THE WATCH ADJUSTER'S MANUAL. 

tions, and more rounding, or in shorter bends, to quicken the 
short vibrations. In altering the form, it facilitates the work 
to have the terminal so made that a portion of it can be 
changed, with a minimum of change in the remainder, instead 
of having to re-form the whole terminal to suit the part changed. 
To illustrate, I reproduce in Fig. 36 the curve shown by 

Phillips, in which the part between 
b and d can have its form considerably- 
altered, without requiring anything 
more than a little bending at the points 
b and d to relieve the rest of the 
spring from any displacement or 
strain. This facility of manipulation 
is its only saving quality, but the 
length oi b d should be made much 
less than e d^ to avoid their being so 
nearly balanced, and make the terminal more positive in its 
action. The Breguet spring is used for pocket watches, in 
which the short arcs are always slow, hence it is a mistake to 
introduce a minus curve b d into the terminal of a Breguet spring, 
because that only adds to the loss caused by the frictions, etc., 
and increases the total error to be corrected by the plus part of 
the terminal. 

(605.) A djusti fig by minus terminals. — In changing the minus 
curve, an increase of length increases its specific action, and 
vice versa^ as it does with a plus curve; but its specific action 
being the reverse of that of a plus curve, the effect of the 
change is also the reverse, /.^., making a minus curve longer 
makes the short arcs slower, and decreasing its length makes 
them faster. The reason is, of course, that the longer the 
curve is, the greater is the virtual lengthening of the spring 
caused by it, in the short arcs — and vice versa. And making 
a minus curve flatter virtually lengthens the spring and makes 
the short arcs slower, while making the terminal more curved 
quickens the short arcs. But the effect of altering the form is 
much less than that of changing the length. 

(606.) Action of Breguet over coil. — The overcoil maybe either 
wholly or partly formed into a terminal curve. If a part of the 
overcoil continues in the normal direction and position of the 
outer coil of the spring, with the exception of being raised above 
the level of the other coils, it still remains a part of the body 
of the spring, and not of the terminal. The terminal curve in- 
cludes only that part of the overcoil which is bent out of its 
normal spiral position or curvature. In forming such terminals. 



THE WATCH ADJUSTER' S MANUAL. 251 

the same rules prevail as with cylindrical springs. The action 
is the same as there described, and they are adjusted in the 
same way. The fact that many of the regular coils of the spring 
are more curved and more rigid than the terminal, does not 
change the principle involved. 

(607.) It is sufficient for us to know that the curve is either 
more or less curved than it would have been in the normally 
formed outer coil, and that it will in consequence act differently, 
and according to the rules already given for the terminal curves 
of cylindrical springs. If a Breguet overcoil is formed as shown 
in Fig. 2^6^ for example, the part e d wAW be more rigid, and db 
less rigid, than the outer coil, and that is enough to tell us what 
the action of each part will be. When we consider the inner 
end of the flat spiral, the inner coils are even more curved and 
more rigid than any part of the terminal, and this fact undoubt- 
edly affects the isochronal action of the spring, just as a termi- 
nal would at that end. Doubtless, too, this matter of the rela- 
tive rigidity of different parts of the spring has something to do 
with the isochronal action of springs whose coils become further 
apart at the outside, of those which are pinned in even or frac- 
tional coils, etc. But as that is a theoretical point not necessary 
to discuss here, and having already exceeded the limits assigned 
to this subject, I will content myself with saying that the in- 
structions already given are all that are needed for practical 
work. 

(608.) Experts' opinions differ. — Before stating the latest and 
most approved practice in terminal curves and the method of 
pinning springs having them, I thought it well to consult some 
of the leading working experts and learn what conclusions their 
experience had led them to consider as reliable. I did so, with 
the result — the usual one, by the w^ay — that I got about as 
many different opinions as there were experts. For instance, 
in reply to questions as to what letigth of terminal curve in the 
Breguet spring they had found to be best, one said it should be 
as short as possible and keep its shape; another, that as a rule 
the best results are obtained from long terminals. With regard 
to the best method of pinning the Breguet spring, one said the 
rule was to pin them \ over full turns, while another said that 
they might be full turns or a half turn; and so it went with all 
the other points asked. Also, see Chapter VIII on the usages 
in the American watch factories. 

(609, ) No one method can meet all cases. — What inference should 
we draw from all this? Simply that there is no rigid rule, but 
that different forms and methods are required in different cases. 



252 THE WA TCH ADJUSTER'S MANUAL. 

Each expert gave rules suited to the kind or class of work he 
was in the habit of doing. As I pointed out and insisted more 
than twenty years ago, and repeated in The Practical Treatise^ 
perfect isochronism is only to be obtained by a special adjustment 
to suit the peculiarities of each watch. The truth is to-day, 
as it was then, that there is no rule or method whatever which 
will certainly secure isochronism in all cases. The most that it 
can do is to secure a more or less close approximatio7i to isochron- 
ism at the outset^ and thus abridge the time and labor of the ad- 
justment. Where great numbers of movements are made pre- 
cisely alike, as is done by the American watch companies, a 
minute tabulation of the results given by different springs will 
enable them to select some particular form, method of pinning, 
etc., which will, /;/ cojinectioji with similar movements^ secure an 
approximation close enough for all ordinary purposes. But 
when the finest time is required, the American manufacturers, 
like all others, depend upon special adjustment. 

(6 10.) The result will depetid iipoji the skill of the adjuster. — 
While the reader will have before him a carefully considered 
and classified epitome of all that is known to the trade, stated 
in form suitable for practical use by practical men, the rules 
given do not secure perfection. No rule can do that, nor will 
ever do it, so long as watches and workmen fall short of per- 
fection. But they will enable him to obtain in a few minutes 
results which otherwise might require hours or days of labor; 
to do even his cheapest jobs in a thorough and workmanlike 
manner; and, in fine work, to produce an excellence of per- 
formance in proportion to his patience, thoroughness and skill. 



CHAPTER XXXIII. 

ISOCHRONIZING THE CYLINDRICAL SpRING. 

(6 1 1.) Selecting the spring. — The workman will generally find 
it necessary to make his own spring, for which instructions are 
given in Chapter VI, Part Second. Standard sizes are some- 
times sold, however, ready made in the cylindrical form — espe- 
cially the new palladium springs. The proper size, number of 
coils, etc., are given in Chapter XXVIII, Part Fifth. Having 
obtained a suitable spring, you cut off the ends that were held 
during the making, till you find the wire is in perfect condition, 
and form your first terminal curve on the end, to go into the 
collet. Having then taken the proper number of coils to the 



THE WATCH ADJUSTER' S MANUAL. 253 

upper end, you also form that terminal curve, taking care to 
leave some surplus spring. The number of coils may be varied, 
to secure the proper number of vibrations per minute. If the 
number to be used is already settled, the spring can be tested, 
to find whether it will give the correct number of vibrations, by 
pinning one end in the collet and holding the upper end in the 
holding tool. Fig. 11, (238,) before that end is bent into form. 
The upper coil can thus be shifted through the clamps and tried 
at different points, without marring or injuring the wire, or even 
bending it until it has been tested both for correct time and for 
its isochronal action. By following the rules already referred to 
in regard to mode of pinning, etc., it will be nearly isochronal. 

(612.) Fortning the terminal curves is done by means of the 
tweezers shown in Fig. 18, (249,) for small springs to be used in 
pocket watches. The heavier springs of box chronometers re- 
quire to be manipulated with pliers made in a similar way. As 
shown in Fig. 18, the tweezers (or pliers) are lined with brass 
blocks, a convex block fitting into a concave one, and both turned 
in cylindrical form, not filed, for it would be difficult to file the 
curves true and parallel. If not correct, they would twist the 
ends up or down, instead of curving them directly inward. Sev- 
eral different tweezers may be used, having different curvatures, 
to give the terminals the desired forms. One pair having the 
same curvature as the body of the spring is used to hold it by, 
while being curved with another. The curves can be bent cold, 
especially if the temper is a very dark blue, or still lower, but 
the spring has to be bent considerably more than it is intended 
to be, as it springs back when released. If the temper is higher, 
it is better to heat the pliers (or tweezers) and hold the spring 
in them till the block cools, and the spring will remain in nearly 
the form so given to it. 

(613.) Heating the tools. — The heating can be done in the alco- 
hol lamp or otherwise, observing that the heating of the tool 
in the lamp, and the working of the spring upon it, must not be 
ventured at the same time. Some workmen use an iron block 
a couple of inches square, having holes drilled into it for insert- 
ing wires of different sizes, changeable as needed. They heat 
the block on a stove or in a lamp till it turns a dark blue, then 
put it into a wooden block cut out to receive it, with a cover 
having holes bored for the forming wires to pass through into 
the block. This wood casing not only protects the hands from 
injury, but keeps the block from cooling off too rapidly. 

The springing open of the tweezers and the weight of the pliers 
will secure good contact and speedy heating. The tools are 



254 THE WATCH ADJUSTER'S MANUAL. 

left resting in the block when not in use, so that they are 
always ready. Screw clamps are sometimes used for bending 
the curves. 

(614.) Use of the forming tools. — Whatever tool is used, it 
must not be too highly heated, as it will reduce the temper of 
the spring too low, and even ruin it entirely by causing it to 
curl up out of all shape. It is not absolutely necessary that the 
heat should be sufficient to even color the spring, although it 
facilitates both the bending and the setting. Yet the heat may 
be considerable without affecting the color, as steel may be 
raised to about 425° Fahr. before a change of color takes place; 
at 450° the article will take a straw color; at 500°, a brown; 
at 530°, a purple; at 575° to 600°, the different blues. The form- 
ing wire or tool should be of steel, or, if of brass or other metal, 
a hardened steel screw should be planted in it as a color-piece, 
(81, 82,) to indicate the temperature. The heat should never 
be greater than will give the color-piece a dark-blue shade. If 
the hair spring is of a lighter shade, the color-piece should not 
go beyond that shade, else the terminal curve will be reduced 
lower than the rest of the spring. 

(615.) If repeated heatings are necessary, the color-piece 
should not reach the shade of the spring, (81). If the spring 
is a dark-blue, the color-piece should then not go below a 
purple, either removing the spring at that stage of the pro- 
cess, or taking the forming wire from the block and quenching 
the whole in alcohol. If the spring is fine, or the heating is 
done very rapidly, from the block being large, too hot, or any 
other reason, great care must be used to avoid reducing the 
temper of the spring too much. The color-piece, or that part 
of the wire which you brighten up to show the color, should be 
very near where the hair spring is held by it, and before the 
spring is put into it at all, the heat should be ascertained. If 
the color goes beyond the blue, the block or tool must be cooled 
a little till it does not exceed the proper shade, when it may 
safely be used. Many workmen are partial to rather high heat, 
but those who have not plenty of experience to justify them in 
using it are recommended to never use a heat above straw color, 
as that is ample for all purposes. A spring held over an ordi- 
nary round broach at that heat will retain its form when cold. 
As every different tool requires different management, I will 
not give more specific directions, but recommend the workman 
to make the best he can afford, and experiment a little on an 
old spring, and he will learn more about it in a few minutes than 
I could explain in several pages. Be sure to compare your 



THE WATCH ADJUSTER'S MANUAL. 



255 



Spring often with the gauge, see that it fits withoiU pressure^ 
using the eyeglass to insure accuracy. 

(616.) Gauge for forimng curves. — Do not attempt to form a 
curve "by eye." Having settled upon the form it is to have, 
draw the curve, in its exact shape, size, and position relatively 
to the outer circle of the spring, upon cardboard, in ink, or 
upon a thin sheet of brass or copper which is filed down to the 
outside of the curve on that side — and use that as a guide or 
templet, comparing the spring with it frequently, by the aid of 
a strong glass. You first measure the diameter of the spring 
through the center, lay off that distance on paper with the di- 
viders, set the points to just half this distance, and with this 
radius mark a circle corresponding to the outer circle of the 
spring. Draw a line across it, exactly through the center, and 
another exactly at right angles to it. These are guides in 
marking the curve upon it, and also in comparing the spring 
with it when marked. Let the end of the curve be exactly at 
one of these lines, half-way from the centre to the circle, and 
also marked where the "junction" is to come, then draw the 
curve between those points, and file off the metal outside of 
the curve. Whenever you change the curve, in adjusting, this 
gauge will show you what you have done. Make every part 
perfectly clear — the circle, the curve and the lines. 

(617.) The proper forms for the curves. — It is, of course, im- 
possible to tell beforehand what form is required, except in 
cases where custom rules. In chronometers of ordinary types, 
similar curves will be needed in similar movements. For a 
marine chronometer, with heavy balance, slow vibrations, and 






Fig. 37. 



Fig. 38. 



Fig. 39. 



with the short arcs fast, the terminals should be minus curves. 
Fig- 37 shows a spring with extremely well formed terminals 
for such a case. The entire length of each curve is minus, ex- 
cept a very short portion at the turn or corner between c and d^ 
which is plus, while from <^ to ^ and from ^ to ^ is minus. Such 



256 THE WATCH ADJUSTER' S MANUAL. 

a curve could easily be lengthened between c and the outer coil, 
and so made more minus, by making the turn c d 2i trifle sharper. 
The reverse change could also be easily made. In Fig. T)^ is 
shown the lower terminal, and in Fig. 39 the upper one, of a 
spring suitable for a pocket chronometer, in which the short 
arcs will nearly always be slow. It will be observed that the 
whole of these two terminals is plus, as it should be in such a 
case, and could easily be made more plus by lengthening them. 
Both of these springs (four terminals) may be accepted as mod- 
els of good construction, for the two types of timepieces. 

(618.) Pinning the spring. — The curves being formed, you 
broach out the hole in the collet inclining upward, so that it 
will hold the spring in proper position. Try this frequently, by 
temporarily pinning in the stud, till it stands true with the 
broach on which the collet is held. The spring must not be bent 
to get it true, but unpin it and change the hole till it will stand 
true naturally. Make the pin round, of the same taper as the 
hole, file away about one-third on one side to go next to the 
spring, and fix it in tightly. Then put the collet on an arbor, 
and try it in the calipers to see that the spring stands perfectly 
true. Drill and broach the upper hole, with the proper inclina- 
tion and position so that the upper curve will stand naturally and 
freely in the hole, fitting both the hole and the pin to it with 
the same care as the lower end, to see that it is perfectly free 
from constraint when tightly pinned at both ends. 

(619.) Lengths of the curves. — The upper curve should occupy 
nearly three-fourths of a circle, for a marine chronometer, and 
the lower curve (collet curve) a little less than a half circle, or 
two curves of half a turn each for short springs, so that the 
spring will be pinned in even turns for long springs, or down to 
one-fourth turn short of even turns when the spring is short. 
In pocket chronometers the upper curve should generally be 
about three-fourths of a turn, and the lower one nearly a turn, 
— the ends being pinned in even turns. These lengths are by 
no means obligatory; they are used by good makers, but others 
use very different lengths and modes of pinning. What is best 
in any particular case can only be told by actual trial. The 
lengths of the curves can be changed as required, and be made 
longer or shorter as well as changed in form. 

(620.) Length of the spring. — But it is evident that the length 
of the spri?ig cannot well be changed after the curve is made, 
because the coil is inclined upward and the end at the stud 
would then stand too high or too low to come naturally and 
freely in the hole. By considerable labor, a change of length 




THE WATCH ADJUSTER'S MANUAL. 257 

might be allowed for, but the trouble is so great that the workman 
should never form the upper curve and fit it to the stud until 
he has timed the spring sufficiently to be certain that it will run 
within a few seconds per day — i.e.^ within limits which can eas- 
ily be corrected by the timing screws in the balance. This 
shows the necessity for some spring-holding tool like that in 
Fig. II for timing the spring before the terminal is bent up. 

(621.) Manner of attachment to the collet and stud. — The ends 
should ordinarily meet the collet and stud at a right angle to 
the radius passing through them, — i.e.^ to the face of the collet 
or stud — or tangentially. But some makers pin the 
upper end in a different way, viz : When the short 
arcs are too quick, in a marine chronometer, the 
spring is bent a little outward, i.e.^ the end is bent 
more outward from the center, to make the short 
arcs slower. In Fig. 40, e is where the end of the 
terminal meets the stud, and e b shows the direction 
of the end according to the general rule, while e c 
is the inclination given to it as just stated. The 
pin is then placed on the inside or right. Others ^iq 40"" 
do this bending in the opposite direction, in pocket 
chronometers, where the short arcs are too slow. If e represents 
the end of the terminal of a pocket chronometer, e b would be 
the direction it would usually have at the stud, while c d would 
be the direction given to it to quicken the short arcs. 

(622.) Effect of changing the direction at the poi?it of attachment. 
— If the reader has understood my explanation of the action of 
terminal curves, he will perceive that bending the portion near 
e to the left makes that part more minus, and that causes the 
slowing of the short arcs; while the bending of the portion near 
the stud to the right makes that part more plus, which accounts 
for the quickening of the short arcs. Both practices are there- 
fore in conformity with the law of terminal curves already laid 
down. But I cannot consider them commendable, for the same 
result could be better obtained by changing the length or shape 
of the terminal. When this method is followed, only the end oi 
the terminal is bent, just at the point of pinning. 

(623.) General arrangement. — The forms of the curves and the 
relative positions of the two ends of the spring must be such 
that any tendency to displace the spring in one direction will 
be counteracted by a tendency to draw it in the opposite direc- 
tion. Whether these tendencies do balance each other, can only 
be told by carefully watching the movements of the spring when 
in action, or by timing it in positions. 
17 



258 THE WA TCH ADJUSTER'S MANUAL. 

(624.) Changing the curves. — When the curves require to be 
changed in the process of isochronizing, the method is the same 
as for originally forming them. Pliers or tweezers of greater 
curvature are used to make them more plus, and those of less 
curvature or flat to make them more minus. The effect of a 
curve is in proportion to its length, and, in a lesser degree, to 
its curvature. Hence, to increase its specific effect, increase its 
length; and increase the curvature of a plus curve but decrease 
that of a minus curve. To lessen its specific effect, take the oppo- 
site course. For example, if a watch loses in the short arcs, 
make the plus terminal curve longer or more curved ; to make the 
short arcs slower, make its curvature less or the terminal shorter. 
When a curve is made longer, some of the body of the spring is 
taken into the curve and its total form made such as will be in 
harmony with the service required ; if a curve is made shorter, 
a part of it is bent back into the form of the body of the spring, 
and the remainder made regular and proper in its curvature. 

(625.) Return of fortn. — Springs, after a change of shape, 
have a tendency to return more or less to their previous form, 
and this settling back must be first gone through with before 
permanently trustworthy tests of the effect of the change can be 
made. In the preliminary and coarser alterations, the test may 
be had at once, but as we approach closer to correctness it will 
be necessary to wait at least three or four hours, or over night, 
before testing. The watch should be kept running during the 
settling-back process, as the vibration hastens the completion 
of the change in the spring. It is advisable to anneal a spring 
after it is finished, also, after it is changed in form, to avoid the 
risk of havingit gradually alter its shape and rate while running. 
It can be annealed in any convenient way, one being to heat it 
in an oil bath to about 212°, or the temperature of boiling water, 
for the final annealing. 



CHAPTER XXXIV. 

Isochronizing the Flat Spiral Spring. 

(626.) Selecti?ig the spring. — Taking a spring of the breadth, 
thickness and temper which the old one had, or which you deem 
suitable, and of apparently suitable strength, try it for size, by 
laying it on the inverted balance cock. The size should gener- 
ally be just right to lie naturally between the regulator pins and 
in the stud hole, and at the same time be concentric with the 
balance jewel hole. But if the kind of watch you are working 



THE WATCH ADJUSTER'S MANUAL. 259 

at is known to be addicted to losing considerably in the short 
arcs, it is better to have the spring a little small, so that it will 
not be concentric at the jewel hole, but its center will come a 
little towards the stud. That will make the short arcs quicker 
and so balance the customary loss. 

(627.) Testing the spring. — Having one apparently suitable, 
seize the coil which lies in the regulator pins and over the hole 
in the stud, at a point midway between the regulator and the 
stud, and mark the point with a speck of whiting and oil. Fas- 
ten its centre concentrically to the balance staff with putty pow- 
der, and find the number of vibrations it gives, as directed in 
Part Fourth. If the number of vibrations is correct, after al- 
lowing for the amount which will have to be broken out at the 
centre to fit the collet properly, and holding the outer coil at a 
point which has the proper position relatively to the collet end, 
(z>. , even turns or otherwise, according to the kind of escape- 
ment, as directed in Part Fifth,) and also such as will give the 
spring the proper size or freedom, (626,) proceed to fit it properly 
to the collet and pin it securely. 

(628.) Timitig the spring. — Put the spring and collet on the 
balance staff, and again try the vibrations more closely, either 
with the timing balance or in the watch, using one of the spring- 
fitting tools described in Chapter XVII, or something similar, 
instead of pinning it in the stud. If the vibrations are within 
the limits which can be regulated for, put the balance in the 
watch, (if not already done,) screw the balance cock in place, but 
hold the spring in the claws of the fitting tool instead of the 
stud, which should be taken out of the way of the spring. If 
you have no such tool, you will of course have to pin the spring 
in the stud. The next thing is to get the rate tolerably close, 
in the horizontal position which will be employed in the position 
trials. If the watch is to be adjusted for positions, that adjust- 
ment comes next, as already stated, after which the isochronal 
adjustment should be attended to. 

(629.) Adjusting for isochronism. Effect of Jorm. — In adjusting 
the flat spiral spring, there are several ways which may be em- 
ployed, if necessary. (See Chapters XXXI and XXXII.) The 
best way is by plus or minus curves. The reader may be some- 
what astonished at the mention of terminal curves in connection 
with the flat spiral spring. But it is a fact that we have what 
are substantially equivalent to terminal curves, and which I 
think he will be willing to call by that name after he has read 
the following explanations: In a spiral spring which is uniformly 
coiled and curved, any part of it is "minus" relatively to the 



26o THE WATCH ADJUSTER' S MANUAL. 

portion nearer to the center than itself, and " plus" relatively to 
portions further from the center. Every coil and part there- 
fore acts differently, according to its form and relative rigidity, 
and the action of the spring as a whole is the joint resultant of 
the actions of all the parts and curves in its entire length. That 
result is that there is a certain point in every coil, at which the 
spring, if properly pinned, will perform large and small vibra- 
tions in equal times. That point depends on the form of the 
spring or of its curves, and it can be changed by a change of 
form, because a change of form is a change of rigidity and of 
action, and changes the resultant action of the spring as a whole. 
Whenever any part of the spring is given any unusual form, or 
bent out of the normal spiral, and even when it is simply taken 
up or let out at the stud, the effect produced is governed by the 
law of terminal curves as already laid down. By looking at the 
subject from this point of view, many seeming inconsistencies, 
irregularities and mysteries will be found to be in strict con- 
formity to that law, and the methods of isochronizing will be- 
come intelligible and clear. 

(630.) Effect of taking up or letting spring out in stud. — As re- 
gards the effect upon the isochronal action of the spring, letting 
it out is equivalent to putting on a minus terminal of that 
length, which, being less curved and less rigid than the contig- 
uous part of the coil, makes the short arcs slower than the long 
ones, and at the same time the additional actual length of the 
spring makes both the long and short arcs slower, (561.) But 
if there is a crimp or stiff part in the portion let out, that of 
course acts as a plus curve, and lessens the effect produced by 
the letting out. Taking up the spring will obviously have the 
contrary effect, both in specially accelerating the short arcs, and 
also making both long and short arcs quicker. Taking up \ or 
\ turn of spring, is equivalent to cutting off that length of minus 
curve, and, so far as the short arcs are concerned, is equivalent 
to substituting a plus curve in its place. The difference of 
rigidity spoken of being small, the isochronizing effect will also 
be small, but it increases more rapidly than the length taken up 
or let out. 

(631.) Effect of bendifig the spring. — It is obvious that if, after 
taking up the spring, we bend the portion near the stud in such 
a way as to make it less curved and less rigid than before, that 
whole portion will be equivalent to a minus terminal of the same 
length, and will make the short arcs slower. The effect of this 
bending may easily be to retard them more than the taking up 
of the spring accelerates them — in which case the result would 



THE WA TCH ADJUSTER'S MANUAL. 261 

be the reverse of that intended to be accomplished by taking up 
the spring. This result is so common that it has given rise to 
the adjuster's rule mentioned in section (563). 

(632.) Effect of bendi/ig the spring toward the stud. — This may 
perhaps explain why the customary setting of the spring " close 
to the stud" prevents the short arcs from being slow; also, why 
a spring too large, in proportion to the position of the stud and 
the regulator pins, will lose in the short arcs. The spring is 
made to " set close" by bending the half turn next to the stud, 
giving it a more rapid curvature, which of course makes it act 
as a plus terminal and quickens the short arcs. In Fig. 41, 
the full line shows the natural position and shape of the outer 
coil, concentric with the axis at ^, and the broken line shows 
how the outer coil would be bent inward, from/ to/', in order 
to throw the spring nearer to the stud e. The fact that it does 





Fig. 41. Fig. 42. 

quicken the short arcs, (575,) notwithstanding that the side fric- 
tion produced on the balance pivots makes them slower, shows 
that the effect of such bending is much greater than the contrary 
effect of the side pressure — doubtless because from e to-/ is a long 
terminal. The result is not due to its proximity to the stud, 
but to the excentricity of the spring, no matter on which side of 
the center that may be. 

(633.) Effect of fitting the spring excentrically. — Sometimes the 
spring is a little small for the stud and regulator pins, and nat- 
urally stands close to the stud, without requiring any bending 
to bring it there, — as shown by the full line in Fig. 42. In such 
cases the short arcs do not lose nearly so much as they would 
if the spring was bent to the position shown by the dotted lines, 
to make it concentric with the balance axis a. Most workmen 
would say that the spring acted better in the former case {i.e.^ 
it lost less in the short arcs,) because it retained its natural form, 
as well as from it being close to the stud. But according to the 
principles I have been explaining, the reason is altogether dif- 



262 THE WATCH ADJUSTER'S MANUAL. 

ferent from that. Let us suppose that the natural form of the 
spring had been as shown by the broken line, and that we had 
bent it to the form of the full line. It is perfectly clear that the 
arc ef would then have acted as a plus terminal, and would 
quicken the short arcs. Reason tells us that the action of the 
terminal is due to its length and form, and that it matters not 
whether it was bent into that form by the spring maker or by 
the adjuster. 

(634.) Actions of terminals compat'ed. — Let us now consider 
these two terminals in Fig. 42, solely from what we know of 
their actions, the rest of the spring being the same in both 
cases. As compared with ef, ef is a plus terminal, and it 
makes no difference when it received its form. According to 
established horological laws, we ought to bend it into the form 
ef, and bring the body of the spring concentric with a, to 
make it correct. If we prefer to use the form e f\ the effect will 
be the same as if we had bent it into that form, i.e., it will make 
the short arcs quicker than ef will. That is the true explana- 
tion of the action of excentric springs. As regards the side 
pressure, there is no doubt that the side pressure compresses 
one side of the inner coils and expands the opposite halves, but 
we may probably say that these opposite effects will practically 
balance each other. At any rate, it is safe to consider such 
effects as of small importance compared with those of the ter- 
minals, inasmuch as the terminals show their characteristic ef- 
fects over and above those of all other influences. 

(635.) The effects are due to departure from the normal spiral 
form. — The effects of different curvatures or forms are due to the 
forms themselves, no matter whether they were made into those 
forms by the spring maker or by the adjuster. Disregarding any 
minor effects due to change in the texture of the metal caused 
by bending, etc., we may say as a general principle that the 
action is due to the departure from the normal spiral form of the 
spring. If the normal spiral form in Fig. 42 is ef, the form ef 
is a plus curve, no matter how it received that form; if e f is 
the normal form, then any variation from it in the direction of 
ef will act as a minus terminal. If that is true, it follows that 
any change from the normal spiral form, whether at the outer 
or inner end, or elsewhere, will affect the isochronal action of the 
spring according to the rules before laid down. This will ex- 
plain the action of the inner end when it does not leave the 
collet in the true spiral form. But I will not occupy more space 
with that point, since it is never advisable, and never necessary, 
to alter the inner end for isochronizing purposes. That end 



THE WATCH ADJUSTER'S MANUAL. 263 

should always be properly formed and pinned in the collet, let- 
ting all isochronal alterations be made at the outer end. But 
the effect of changes or improper forms anywhere in the length 
of the spring may be known from the following: — 

{(i2>^.^ Rules for the isochronal adjustmefit of the flat spiral. — 
Any portion which is more curved, stiff and rigid than it was or 
would be in the normal spiral form will act as a plus curve, to 
quicken the short arcs, and vice versa. Any increase in the 
length of such a curve increases its effect. If it is a plus curve, 
making it longer will make the short arcs faster, and vice versa; 
if it is a minus curve, increasing its length will make the short 
arcs slower, and vice versa. The absolute amount of change 
produced will of course depend on the conditions in each case. 

If the adjuster will keep these cardinal principles in mind, the 
process of isochronizing the flat spiral should be plain sailing. 



CHAPTER XXXV. 
Isochronizing the Breguet Spring. 

(637.) The Breguet hair spring. — What is called the Breguet 
hair spring is a flat spiral provided with a terminal curve at its 
outer end, which is raised up by means of an elbow or bend, so 
that it can be returned towards the center over the other coils. 
As we have seen, all flat spiral springs which are desired to 
possess isochronism should be as long as possible and closely 
coiled, as the angle of inflexion of each coil will be thereby 
reduced, its action will be more uniform and easy, and it will 
have less tendency to be forced out of center and exert a side 
pressure against the axis of the balance. This is particularly 
important with the Breguet spring, which should be broad and 
flat, the coils very close together and more numerous than for a 
plain spiral of the same diameter. It is usual to give the Breguet 
from one-third to one- half more coils than the plain spiral would 
have in a similar situation. Being so close, the least injury or 
irregularity in the coils renders the spring worthless for fine 
adjustments. The American watch companies use the same 
number of turns as for the flat spiral, namely, about fourteen 
coils. See (105), Chapter XVIII. 

(638.) Selecting and fitting the spring. — The process is the same 
as for the flat spiral. To test it, by finding whether it will give 
the proper time, which must of course be done before the over- 
coil is bent up, it is indispensable to have some spring-fitting 
tool. The outer coil, not being yet bent in, cannot be held in 



264 THE WATCH ADJUSTER'S MANUAL. 

the stud. It is therefore gripped in the clamps of the spring- 
holder while timing. When one is found of suitable strength, it 
is pinned to the collet and again more closely timed, as directed 
for the flat spiral. The point held in the clamps, when it gives 
correct time, will when the overcoil is bent towards the center 
reach a quarter of a turn further around the center than before, 
i.e.^ i3f turns when held in the tweezers will make 14 turns 
when bent in, and will then make even turns, which is consid- 
ered the proper method of pinning for Breguet springs. As 
the Breguet spring is liable to prove more slow than expected, 
it should gain slightly when held at the point which makes i3f 
turns before bending. But if it should nevertheless lose, it can 
be broken out at the center a little if necessary. Next should 
come the position trials, if the watch is to be adjusted for posi- 
tions, the spring being held in the clamps of the spring-holder 
at the correct time point, as directed for the plain flat spiral. 
Being assured by the position trials that our spring will not re- 
quire to be changed, we now form the overcoil. 

(639.) Length of the overcoil. — The overcoil is generally made 
one turn in length. Before deciding whether the spring will be 
suitable, hold the outer coil rigidly in the tweezers at a point 
one turn from the point where it was held when it gave correct 
time, and spring {not bend) that coil around the center in such a 
way as to bring the correct time point to the stud hole. This 
w^U show, very closely, how much further the correct-time point 
will reach around the center after the terminal is formed. 

(640.) Position of the elbow. — We have now to consider the 
position of the elbow. It is generally supposed that the placing 
of the elbow correctly is a point requiring great experience and 
judgment, and renders the making of a Breguet spring a very 
difficult and complicated job. The exact position of the elbow 
is not an essential matter, its object being merely to raise the 
final or supplementary coil so that we can curve it towards the 
center as* we find needful, without interfering with the other 
coils. The terminal curve need not begin at the elbow, unless 
we find it necessary, upon trial, to make it so long as to reach 
to that point. The curve may begin at any distance from the 
end of the spring which will secure isochronal vibrations. The 
position of the elbow has nothing to do with that adjustment, 
provided it is far enough from the end of the spring to be out 
of our way. It simply, on the flat spiral, enables us to enjoy 
the same freedom in forming the terminal curve that we have in 
the helical spring. 

{641.) Action of the elbow . — My meaning will be more evi- 



THE WATCH ADJUSTER'S MANUAL. 265 

dent by supposing that, with the exception of the outer coil 
being raised up by the elbow, no change has been made in its 
shape, the outer coil having the same size and distance from 
the center as before. The spring would therefore perform 
nearly the same as before, except so far as this elbow has made 
it shorter and stiffen Accordingly, whether the elbow is a half, 
three-quarters, or whole turn from the end makes very little 
difference practically, although it is considered well to make it as 
near the end of the spring as will give room for the terminal 
curve. That is the real means of securing isochronism, not the 
elbow. The stiffness of the elbow is, of course, a disturbing 
influence or cause of irregular action in the spring, to a certain 
extent, but it is unavoidable, and we must correct or neutralize 
its effect in our adjustment of the terminal curve, along with all 
other unavoidable irregularities, such as resistance of the air to 
the balance, unequal springing out of the sections of the rim 
by centrifugal force, effects of friction in the balance jewel 
holes and the escapement, the oil, mechanical imperfections of 
all kinds, in the spring itself, as well as elsewhere — so that in 
spite of all of them the vibrations shall be isochronal, or as 
nearly so as we can make them. Many workmen insist that 
the supplemental coil must be just one turn in length, from the 
elbow to the stud. It will be noticed that following my direc- 
tions will generally make it so. But that length is not impera- 
tive, for it may be either more or less, without harm. Instead 
of a single supplemental coil, some workmen have used two, 
three, or even more coils. 

(642.) Making the elbow. — The usual way of forming the 
elbow is to make two bends in the outer coil of the spring, one 
causing it to rise above the level of the other coils, the other 
bending it down again and making it parallel with them, but on 
a higher plane. The spring must not be twisted sideways to 
throw the overcoil up or down, but the coil must be kept truly 
vertical, as it was made, and actually bent, edgewise, i.e.., one 
edge will be stretched and the other compressed a little. This 
strains the metal, and is to some extent injurious; hence the 
bend should not be too abrupt. The American watch com- 
panies employ a gradual incline extending some distance along 
the spring, in place of the usual more abrupt elbow. That is 
less injurious to the metal, but if the incline is too long it 
causes more or less side twisting during the vibration. 

(643.) Tool for ?naking the elboiv. — This is done very easily 
and quickly with a pair of tweezers such as described in section 
(250.) As the tweezers hold the coil firmly and flat while bend- 




266 THE WATCH ADJUSTER'S MANUAL. 

ing it, any side twist or doubling up at the bend is prevented. 
The first bend is made a little more than one turn from the cor- 
rect time point, giving the coil an upward inclination considered 
suitable, and, at a point which will secure the proper clearance 
for the overcoil, it is bent down. The tweezers are preferably 
heated, and the part to be treated must get thoroughly warmed 
up before bending, then held till cool. With care, even the 
hardest spring can be safely bent in this way. The novice 
should first practice a little on an old spring till he knows what 
is safe, and how to do it properly. 

(644.) Explanatioji of angles. — For the benefit of those who 
do not understand "angles," Fig. 43 is inserted. At the point 

b, a line b d\?> drawn per- 
^ pendicular \.q> ab c <^^ and 

2 the arc of a circle from 

^ <r to ^/ is 90° or one-quar- 
^ ter of a circle. If ^ i is 
« h c ^ drav/n parallel with b c ^^ 

-r-,^ ^^ the line ab d\ will have 

r IG. 43' o 

two angles of 90 , — at b 
and at d. Next measure half the distance from c to d^ and 
from that point draw lines to b and 2; in the line a b 2, 
there will be two angles of 45° each, /.<?., half of 90°. In the 
same way, if we measure any other fraction of c d^ we will get 
that fraction of the angle of 90°. Thus, one-third the distance 
from c lo d will give us the line « ^ 3 having two angles of 30° ; 
one-sixth that distance gives the line ab a^, with angles of 15°. 
These angles are about as abrupt as the spring should be bent, 
although the elbow frequently has more inclination than that. 
It will of course be understood that the part ^<^ corresponds to 
the body of the spring, the incline to the elbow, and the hori- 
zontal part to 4 represents the overcoil. 

(645.) Height and position of the overcoil. — The overcoil is to 
be raised so that there will be, between it and the other coils, 
a space about twice the breadth of the spring. Some give even 
more, but that necessitates a longer elbow and increases the 
amount of torsion or side twist which it produces upon the spring 
when vibrating. The space named gives ample clearance, which 
is all that is necessary. Some good makers give only one and 
a half times the width of the spring, but that is bringing the 
two parts rather close. The less the spring will bear to be bent 
without producing the slightest injury, or the greater the clear- 
ance to be given, the longer the straight portion of the elbow, 
between the bends, must be, and vice versa. After the elbow is 



THE WATCH ADJUSTER' S MANUAL. 267 

formed, if the clearance is found too great, the bends can be 
made a little less abrupt by simply squeezing them between the 
heated tweezers, (249, 250,) or even the jaws of a pair of very 
narrow flat pliers, smooth inside, which by the help of the heat 
flatten the bends and so partly straighten them. The clearance 
must be sufficient to prevent the under coils touching either the 
supplemental coil or the stud, even when subjected to violent 
shakes or thumps. The Breguet spring being long, the middle 
coils are liable to a greater amount of trembling and displace- 
ment by shocks than others, and require a greater space for 
clearance. 

(646.) The supplemental coil must be parallel to the other 
coils. If not, it can be made so by flattening one of the two 
bends. If the supplemental points upwards from the body of the 
spring, flattening the first bend will bring it down. Or, if it lies 
too low, flattening the last bend, or the one nearest the end, 
will cause it to point higher and be parallel. This flattening is 
done by squeezing the spring flatwise, not by applying force to 
its edges. The supplemental may also be leveled by twisting the 
elbow sideways to throw the end upwards or downwards. But 
this should only be done for very slight errors, as the edges 
of the elbow as well as other parts should be truly vertical, /.<?., 
the breadth of the spring-wire should invariably be at right 
angles to the horizontal plane of the spring, and parallel to the 
balance axis. 

(647.) The terminal curve. — The overcoil, or so much of it as 
may be needed, is now to be formed into a terminal curve, to 
make the long and short arcs equal, /.^., isochronal. The 
length of the terminal will depend on the amount of position 
error to be corrected — the greater that error, the longer the 
terminal must be. If the position adjustment has been made, 
as before directed, (638,) you will know the amount of the 
error to be corrected. If the error is dL gain in the short arcs, 
make the terminal as long as you can — f turn to i turn, for 
you will probably need all the length you can get. If the error 
is a loss of, say, 6 seconds per day, in the short arcs, make the 
terminal \ turn; if over that, make it f turn; if over 12 seconds 
per day, make it i turn in length. These lengths are only first 
approximations, and may require to be modified on trial. You 
will of course remember that a minus curve is required to cor- 
rect a gain, and a plus curve for correcting a loss, in the short 
arcs. 

(648.) Ascertaining the positio7i errors. — If the position adjust- 
ment has not been made, time the watch specially to ascertain 



268 THE WATCH ADJUSTER'S MANUAL, 

the position errors — 12 hours in the horizontal position, and 12 
hours in vertical positions, pendant up; or the lengths of the 
trials may be double those stated. The watch should be fully 
wound up at the beginning of each trial, to get the motive force 
the same, and eliminate the isochronal error of the spring from 
the results, so far as possible. From the results thus obtained, 
you can estimate the proper length and form of your terminal 
curve, for a first trial. See section (655.) But, of course, if 
you are working on a timepiece of a certain uniform or stand- 
ard character, which is known to require a certain form of ter- 
minal, you can make your terminal that way. Or if you have 
the old one for a model, which was correct, copy it as closely 
as you can. If not, make a gauge for testing the form (616.) 
The difference per day between the horizontal and one vertical 
position is taken as the position error. 

(649.) Forming the terminal curve is governed by the rules 
already given under the head of the cylindrical spring. (See 
Chapter XXXIII.) The form generally called "the Phillips' 
curve" is shown in Figs. 27 and ^^d. A better form is given in 
F^g- 39j showing a terminal about f turn in length. This can 
easily be lengthened or shortened as needed, as directed for the 
cylindrical spring. 

(650.) Breguet spring vise. — Fig. 44 shows a very convenient 
little tool for holding the spring while working on the terminal. 

It consists of a pair of brass jaws, one 
upright a being fixed in a brass base /, 
such as an old watch plate, while the 

- ^i^ other jaw b is free on the screw d, and 

^ ^^^^'^^^^^^^^^ is drawn towards a by the central screw 

^^' ^^' c. To keep the jaws parallel, a short 

piece of the same spring is put between them at the bottom, 
while the elbow is clamped between them at the top. This tool 
leaves both hands free to work with. The insides of the jaws 
are properly curved to fit the shape of the spring. Two or three 
such vises, having different curvatures, can be arranged in a 
circle of \ inch diameter, with the heads of the screws towards 
the center of the base, and the spring will then be outside, over 
a. The curves of the jaws should be parallel, polished, and 
without sharp edges to scratch the spring, as directed for the 
tweezers. 

(651.) Breguet over coil with a regulator. — I have said that the 
terminal curve of the Breguet spring should be made precisely 
the same as that of the helical spring. This is the rule when a 
regulator is dispensed with. The theory of the terminal curve 




THE WATCH ADJUSTER'S MANUAL. 269 

requires its ends to be rigidly fixed, so tliat the angle at which 
it meet the stud may be as invariable as possible. But when a 
regulator is used in conjunction with a Breguet spring, a new 
element is added to the problem. Whether the regulator pins 
are open or close, they are injurious to the proper action of the 
spring. If they are open, they interfere with the normal effect 
of the curve, by preventing it from flexing and vibrating natu- 
urally and properly. On the other hand, even if the pins are so 
close as to constitute the ideal regulator and virtually become 
the stud, they would derange the action of the curve by chang- 
ing its operative length and its place and angle of attachment to 
the (supposed) new stud. For if the pins were made to conform 
to the position of the curve as they were moved along it, the 
further they were from the stud the further they would be from 
the center of the spring, and therefore the curve would not be 
attached to the supposed new stud at half the radius, as required. 
But if the pins retained their proper distance from the center, 
as they moved along the curve they would draw it to their own 
circle, and obviously force both it and the entire spring out of 
place and entirely destroy the isochronism. This is the usual 
result, when the ordinary Breguet spring is " regulated" by an 
inexperienced workman. 

(652.) The concentric arc of the Breguet spring. — It is common, 
therefore, to form a portion of the last coil, next to the stud, 
concentric, i.e.^ bend it so that it will form a part of a true cir- 
cle, having the center of the spring for its center and half the 
radius of the spring for its radius; as if, for instance, the termi- 
nal curve, dc^cb, Fig. 31, joined on to a concentric, semicircular 
arc reaching from e to d^ and the spring was pinned in the stud 
at <?, instead of at d^ where the terminal curve ends. This con- 
centric portion is sometimes made as much as half a coil in 
length, as just described, and is acted upon by the pins of the 
regulator the same as the outer coil of the ordinary flat spring. 

It is an undoubted advantage to have the use of a regulator 
for rating a watch, and another advantage of having a concen- 
tric portion at the end of the spring is that, if necessary, it may 
be moved through the stud without thereby changing the dis- 
tance of the end of the terminal curve from the center and so 
necessitating a remodeling of the shape of the remainder of the 
curve. 

(653.) Disadvantages of the concentric arc. — But this arrange- 
ment has also its disadvantages. At the junction of the con- 
centric portion and the true terminal curve, the spring is not 
rigidly fastened, as the theory of the curve requires, unless the 



270 THE WATCH ADJUSTERS MANUAL. 

regulator pins clasp it firmly, precisely at that point, and act as 
a stud. But if the pins are in the least open, the yielding of the 
spring at and behind the pins would allow the entire terminal 
curve to move more or less without changing its form at all, and 
during the remainder of the vibration the amount and direction 
of its flexion would be modified by the amount of yielding in 
the concentric portion of the spring behind the pins. This yield- 
ing, in turn, would depend on the position' of the regulator 
between the junction and the stud. The nearer it was to the 
stud, the greater this yielding would be, and it would also in- 
volve the further difficulty that the junction, or real end of the 
terminal curve, would not even be fixed at half the radius, but 
would be at all sorts of distances from the center, sometimes 
further than it should be, sometimes less — and every movement 
of the regulator, nearer to or further from the stud, giving it 
greater or less liberty and scope of motion, would change the 
entire position, condition, and action of the terminal curve. 

(654.) The Breguet terminal curve. — All these difficulties are 
easily removed by abandoning the use of a concentric arc in 
combination with a terminal curve, and use only a terminal 
curve, the end of which, next to the stud, may be concentric 
with the balance axis, as edb^ in Fig. 31, or concentric with the 
regulator center at tz\ as edcb in Fig. 32. There is no more 
objection to the portion e d having a circular form than any 
other, provided that shape can properly be a part of the termi- 
nal curve we require. And if a regulator must be used, it can 
be planted concentrically with that portion. But the spring 
should be timed in such a way that the regulator may be kept 
as near the stud as possible, because shifting it from the stud 
cuts off that length of the terminal curve, and alters its action 
as a terminal. 

(655.) Testing the curve. — Having decided upon the proper 
form for the curve, (647, 648,) and made it so, you will now test 
the spring to find whether that curve will correct the position- 
errors, and if not, how it should be altered. To do this, you 
make two trials, one in the horizontal position, the other in the 
vertical position, (648,) and we will suppose that the error in 
the vertical position was 16 seconds per day loss. You use the 
motive-force controller (673,) if necessary, to get an arc of \\ 
to i\ turns in the first trial, and one of, say, -| turn in the verti- 
cal position — each trial being for 12 hours. Note how much 
the short arcs are faster or slower than the long ones (or hori- 
zontal position arcs), and follow the indications given in the 
table (667) for the proper change to niake in the curve, by the 



THE WATCH ADJUSTER' S MANUAL. 271 

rules given in section (624.) The isochronizing of the spring 
is then completed according to the general rules for adjusting, 
in Chapter XXXVI. 

(656.) Special points about the Breguet spring. — In altering the 
curve, move the spring through the clamps to lengthen or shorten 
the terminal (putting the watch in beat again by merely turning 
the arbor/ around in the head ^, Fig. 11, (238,) sufficiently to 
restore the beat,) until the long and short arcs have the same 
amount of error per day, when the spring will of course be iso- 
chronous, although the watch may still gain, or may lose, in 
both long and short arcs. You now pin the spring in the stud, 
and finish the job. If you have no spring-fitting tool, the ter- 
minal must be shifted through the stud as described, instead of in 
the clamps. When the isochronal point is found, as above, the 
timing must be made correct. If the watch loses, a part of it 
will be corrected by the regulator, (the point which was held in 
the clamps being pinned just outside of the stud,) and the rest 
by altering the mean-time screws in the balance. The latter 
alteration will also correct a gain in the rate. It should also be 
remembered, when fitting with any tool except mine, that the 
spring will be considerably slower when finally bent into shape 
and pinned in the stud than it was when held in the tweezers, 
and proper allowance (from half a minute to two minutes,) must 
be made before bending. The amount can only be found by 
experience in similar cases. 



CHAPTER XXXVI. 

The Isochronal Adjustment. 

(657.) What is the isochronal adjustment! — What does it con- 
sist in ? From what has already been said, and repeated over 
and over again, it must be clear to all that the true object of 
the isochronal adjustment is to produce in the spring an error 
which is equal to and the reverse of the errors caused by fric- 
tions, the action of the escapement, the imperfections of the 
movement, etc. If these disturbing influences cause a certain 
loss of rate in the short arcs, the spring must be so manipulated 
that it will gain that amount, and vice versa. The rate will then 
be correct, the vibrations will be isochronal, and the watch will 
be "adjusted for isochronism." 

(658.) Proper order for the adjust7?ients. — It must also be clear, 
from the foregoing considerations, that before we can adjust for 
isochronism, or know what errors we are required to adjust for, 



272 THE WATCH ADJUSTER'S MANUAL. 

those errors should be reduced to as small an amount as possi- 
ble, the mechanical treatment of the movement finished, and its 
condition be such that the errors which are found to be unavoid- 
able shall not afterwards be increased, for it would be a waste 
of time to adjust for certain errors and then have them doubled 
or greatly increased. It follows from this, that the adjustment 
for positions 'i\iO\x\<\ precede that for isochronism. The position 
adjustment, when rationally conducted, is a process of mechani- 
cally perfecting and adjusting the mechanism, to reduce the 
difference of the frictions, and other disturbing influences, in the 
different positions to the smallest possible amount, and also to 
reduce the error /// any position as low as possible. That is a 
purely mechanical proceeding, governed by the amplitudes of 
the vibrations, and properly has nothing whatever to do with 
timing. The common practice of deferring the positional adjust- 
ment till after the isochronal, and even the compensation, 
adjustments have been finished, is therefore as ill-judged and 
foolish as it would be for the jobber to wait till he has cleaned 
his watch nicely, before he attended to the repairing and 
mechanical alterations. 

(659.) When this adjustfnent may co7ne first. — There is only one 
case in which such a course would be excusable. If the work- 
man is fitting a new Breguet or cylindrical spring, and has no 
spring-holding tools (such as are described in Chapter XVII, 
or something similar,) and cannot make the position tests until 
after he has brought the spring approximately to time, i.e.^ after 
he has ascertained the proper length and made the terminal 
curve, so that he can pin it in the stud and screw the balance 
cock in place, — he will of course be compelled to first do that. 
In doing so, however, he should make no attempt to secure a 
fine isochronal adjustment, because that would consist in get- 
ting the spring to make the short and long arcs in the same 
times, — the watch being kept in the horizontal position, and the 
arcs changed by mechanical means. Such correction of isochro- 
nal errors is a waste of time, because he will afterwards have 
to produce such errors to correct the position errors, and that 
adjustment will thus be destroyed again. But if he has such a 
tool, he can grip the spring wherever he finds it most convenient, 
instead of pinning it in the stud. By screwing the balance cock 
in position, with the stud removed to get it out of the way of 
the spring, he can run the watch in any position, and make any 
tests required, before isochronizing the spring. 

(660.) What the isochronal adjust?nent ca?i acco?nplish. — It is 
well known that this adjustment can only correct a limited error 



THE WATCH ADJUSTER' S MANUAL. 273 

arising from frictions, etc. But this is partly due to the work- 
man himself. According to the common practice, he first gets 
the spring as free from " isochronal error" as possible, (/.^., theo- 
retically isochronous,) and then complains because it cannot 
correct a position error greater than its own — just as if he should 
tie up his hands and then complain that he could not do much 
work. The rational method of adjustment would be to first 
find the nature and amount of the unavoidable position errors, 
paying no attention whatever to getting the spring (theoreti- 
cally) isochronous and correcting its errors, but then increase 
its errors (in the proper direction) till they balanced the posi- 
tion errors. Then he has at the same time corrected the position 
errors and perfected the isochronal adjustment. This will pos- 
sibly explain why such eminent chronometer makers as Mr. Kull- 
berg and others should advocate so improper a course as setting 
the spring excentrically, (575 to 578.) They probably felt the 
necessity of producing an error in some way, which would bal- 
ance the opposite position error; but they did not perceive that, 
instead of removing the isochronal errors of the spring, they 
ought to increase them, and make thei?i correct the position 
errors, instead of the frictions; then, they would seldom need 
to set the spring excentrically. It will probably explain why 
many other practices, known to be wrong, are sometimes ad- 
vised by good workmen. It is evident that when the adjust- 
ment is conducted on such principles as I have urged, it will 
correct greater errors, and correct them more perfectly. 

(661.) What it cannot accomplish. — Many suppose that if a 
spring corrects position errors, etc., in the "long and short 
arcs," it will be isochronous for all arcs. The explanations 
given of the action of terminal curves will show that a spring 
has a different rate for every change of arc, from the smallest to 
the largest. We can make its rate correct in two arcs, say, the 
arcs given when hanging and when lying down, by correcting 
the rate in one position by the timing screws in the balance, and 
that in the other by causing the error of the spring to balance 
the position errors, i.e., adjusting the isochronism for that 
position. That is what is usually done. The rate in the hang- 
ing position is made perfect by regulating, and taken for the 
standard; then the short arcs are corrected by the spring. 

(662.) Example. — Let us suppose that the foregoing adjust- 
ment is done for arcs of f turn and i\ turns, for the short and 
long vibrations, respectively. When the watch is carried the 
vibrations will be made sometimes larger and sometimes smaller, 
by shaking, etc. If it is a going-barrel watch, the arcs will 



274 THE WATCH ADJUSTER'S MANUAL. 

become smaller as the spring runs down, till it becomes neces- 
sary to wind it again. Under various conditions, the arcs might 
be anything from -J- turn to nearly 2 turns. In the two arcs of 
\ turn and i^ turns the error of the spring balances the position 
errors, etc., but it will not balance them /;/ any other arc^ unless 
the position errors increase and decrease with the amplitudes of 
the arcs, in the same ratio that the errors of the spring vary 
with the arc of vibration, and in the contrary direction. If the 
spring loses less and less as the arcs become larger, the position 
errors must cause a gain^ and one just equal to that loss, in 
each different extent of vibration. Such a coincidence may 
never occur, and while the rate may be correct when the vibra- 
tions are just f turn and i\ turns, it will not be correct for any 
other arc. The greater the errors of the spring, the greater 
will be the error of rate in the unusual arcs, for the error of the 
spring varies with the arc, but the position errors would remain 
nearly the same during quite a change in the arcs. This error 
we may call the " middle-arc error," corresponding to the middle- 
temperature error of the compensation. 

{662,.) What this teaches. — We see, therefore, that the isochro- 
nal errors of the spring should be small, i.e.^ differ but little 
in the different arcs; and in order that they may be small, the 
position errors which they are required to correct must also be 
small. The position adjustment should be made as close as 
possible, and the position errors small, then the isochronal errors 
of the spring may also be small, and the smaller their difference 
at the extreme arcs, the less error there will be at other or un- 
usual arcs. This again corroborates my claim that the position 
adjustment should be made perfect before the isochronal adjust- 
ment is begun. In the cases where that cannot be done, (659,) 
the isochronal adjustment should only be carried far enough 
to render it practicable to adjust for positions, (if it is to be 
adjusted for positions,) and that should then be done; after 
which the isochronal adjustment can be finished, as described 
in the following sections. 

(664.) Adjusti7ig for theoretical isochroiiism. — In case it should 
be desired to have the spring theoretically isochronous, or as 
nearly so as possible, for testing purposes, as in section (706), 
first find what the arcs are in the hanging and lying positions, 
then get those two arcs with the watch in the sa??ie horizontal 
position^ in each arc^ and accurately note the rate for each one. 
By this method of testing, position errors and errors of poise 
are avoided, and the frictions are made as nearly equal as can 
be done. It is impracticable to get the errors of the spring 



THE WATCH ADJUSTER'S MANUAL. 275 

alone, free from frictions, etc., for if the balance was not con- 
nected with the movement its vibrations could not be kept up 
nor could they be timed. By testing in the same horizontal 
position and the same temperature for each arc, we reduce the 
extraneous influences to the smallest amount and avoid irregular 
disturbing elements. The rates thus obtained show the behavior 
of the spring in the different arcs, very slightly modified by the 
frictions and the action of the escapement. The isochronal 
adjustment can then be made, in any of the ways already de- 
scribed, to correct the errors, till the rates are the same in the 
two arcs. 

(665.) Finding the variations fro??i theoretical isochronism. — The 
fact that they are the same will not show that the spring has 
the exact progression of force required for theoretical isochro- 
nism, i.e.., that its force increases in proportion to the angle of 
flexion, but it will approximately be theoretically isochronous. 
If we wish to know what the effect of the escapement and fric- 
tions is upon the rate, we can test the spring in a spring gauge 
or dynamometer, alter its terminal till the progression of force 
is correct, then again time it in the watch, getting a second set 
of rates, and being careful to have exactly the same length of 
spring in action as before. The best way to insure that is not 
to remove it from either stud or collet during those alterations. 
Comparison of the two sets of rates in the different arcs would 
show where the variation from the isochronous progression was 
greatest. The spring being now theoretically isochronous, if 
the rates obtained in the different arcs and positions are not the 
same, the deviations from equal rates must necessarily be due 
to the position faults, frictions, etc. 

{(idd.) Adjusting for practical isochronism. — This adjustment is 
for making the spring isochronous when running, no matter 
what the peculiarities of the movement are, which is a very 
different thing from the foregoing. Here it is of no conse- 
quence whether the spring is theoretically isochronous naturally, 
or not, so long as there is no imperfection in the material or 
making of it. Our sole object is to get the same rate in differ- 
ent arcs and positions. 

(667.) Analyzing the observed rates. — In adjusting, we really 
ought to know which is the predominant error in the rates we 
obtain. For instance, if the watch loses 8 seconds in the short 
arcs, there are many possible causes for it. The isochronal 
error of the spring and the other errors (of the movement) may 
vary relatively in many ways, and would require different treat- 
ment in different cases, as shown by the following table: 



276 



THE WATCH ADJUSTER'S MANUAL. 
Analysis of Short Arc Errors. 



Observed 


Error of 




Required Er- 


Change made 


Resulting 


Rate. 


Spring. 




ror of Spring. 


in Spring. 


Rate. 


-8" 


— 4" 


— 4 


+ 4" 


+ 8" 


±0" 


-8" 


— 10" 


+ 2" 


- 2" 


+ 8" 


±0" 


-8" 


+ 2" 


— 10" 


+ 10" 


+ 8" 


±0" 


-8" 


+ 8" 


-16" 


+ 16" 


+ 8" 


±0" 


-8" 


— 2" 


— 6" 


+ 6" 


+ 8" 


±0" 


-8" 


0" 


- 8" 


+ 8" 


+ 8" 


±0" 


-8" 


-16" 


+ 8" 


- 8" 


+ 8" 


±0" 



(668.) As will be seen from the third and fourth columns, the 
error of the spring must in every case be made to balance all 
other errors^ in order to secure the perfect rate of the last column. 
In every case the spring is made to go 8 seconds faster than it 
did in the short arcs, (as shown by the fifth column,) but after 
that is done, the spring must still lose in some cases, while in 
others it must gain, as shown by the fourth column. In the 
former cases, we must not change a minus curve into a plus, 
but merely lessen the effect of the former; in the latter cases 
we must make that change, or make a plus curve longer or more 
pronounced. 

(669.) Separating the different errors. — If the spring has termi- 
nal curves, we can generally tell by inspection whether its error 
is gaining or losing, (see second column,) from the nature of 
its curve, and act accordingly. In other cases, the course I 
have recommended in the position adjustment (708) will solve 
the problem. One series of timing trials is to be made in differ- 
ent positions, with the same motive force each time, and with 
nearly the same arc, i:^ turns, in each position, thus largely 
eliminating isochronal errors of the spring from the observed 
rates, i.e., the difference between the positions is free from 
errors of isochronism. A second series is made in the same 
positions, also with an equal motive force in each trial, but 
with an arc of, say, about f turn in each position. This series 
contain the errors of poise, etc., in addition to the errors previ- 
ously found, but still nearly free from isochronal differences, 
when the positions are compared, owing to all being in the same 
arc. The second series shows the total error which the spring 
must correct. 

(670.) By comparing the same positions in the two series, 
we find the isochronal errors of the spring. For instance, by 
comparing pendant up with long arcs, (first series,) with pen- 



THE WATCH ADJUSTER'S MANUAL. 277 

dant up in short arcs, (second series,) we have the action of the 
spring in different arcs, shown by difference in the rates. So 
with the rates for dial up (or down) in the long and the short 
arcs. Having thus found the position and other errors to be 
corrected, and knowing the characteristics of the spring, it 
should be easy to correct them. These trials were designed to 
assist the workman in discovering the causes of the errors in 
different positions, but they would also be useful in a close job 
of isochronizing. They need not occupy much time, if made in 
only two positions, say, hanging up and dial up (or down,) and 
it is generally done so. 

(671.) Varying the extents of the •inbratio7is. — As it is usual to 
adjust by causing the arcs of vibration to vary considerably, in 
the manner that is most convenient, and accurately observing 
the rate of the watch for an equal period with the long and with 
the short vibrations — in order to test the isochronal action of 
the spring, an easy and effective way of getting arcs of any 
required amplitude is desirable. 

In Marine Chronometers it is generally done by keying up or 
letting down the main spring by the ratchet — making the motive 
force stronger or weaker and thereby changing the arcs. The 
same thing can be done with fusee watches, but not to so great 
an extent, as their mainsprings are generally so short that 
there is little extra length for keying up or letting down. In 
such cases we may change the arcs as follows: Wind the chain 
entirely up on the fusee, hook it to the barrel and key up the 
spring one turn. This gives the weakest force of the main- 
spring, with the chain upon the smallest part of the fusee, where 
the power of the spring is transmitted to the train at the greatest 
disadvantage, so that the vibrations will be very small. We 
then take the time for four hours; or, if that is not enough, 
wind it up and repeat till the desired length of time for the trial 
is passed. Next try it with the chain wound only one turn on 
the fusee, while the mainspring is keyed entirely up. This 
gives the other extreme, or the greatest strength of the spring 
acting on the fusee at the greatest advantage, and giving the 
largest vibrations the movement is capable of. Take the time 
as before, either for four hours, or any desired period, winding 
it up at intervals as needed to prevent running down. All this 
is easily done if the barrel arbor has a good square on its pro- 
jecting end. 

(672.) Usual methods. — The above is an extremely severe 
test, and any hair spring that will bear it may be considered 
practically perfect. The more common method is to wind the 



278 



THE WA TCH A DJ US TER ' S MA NUAL. 



chain entirely up on the fusee, then hook it to the barrel, and 
key up the spring enough to run the watch say six hours; then, 
without disturbing the fusee, key up the spring enough for an- 
other six hours, and so on, till the chain has all left the fusee, 
when the mainspring will generally be properly keyed up for 
the ordinary running of the watch. The times must be care- 
fully taken for each period of six hours, and if the different times 
are alike the spring is isochronous. In watches with going bar- 
rels, the time may be taken first with the spring wound entirely 
up, rewinding at regular intervals to keep up the motive power; 
then with the mainspring wound up only one turn, rewinding 
as before to prevent running down. 

When no other convenient way is available, the watch may be 
tried first in the horizontal, then in the vertical position, and the 
motion of the balance will generally vary enough for our pur- 
poses in the different positions, unless it has been adjusted to 
positions. When the arcs are changed in this way, the sa?7ie 
vertical position should be adopted in each trial, unless there is 
a difference of rate in the four vertical positions, arising from 
defective pivot fittings, want of poise in the balance, etc. If 
so, it will be necessary to divide the time of the trial between 
two opposite vertical positions and take the mean of the two 
in order to neutralize the errors in the opposite positions. 

(673.) Motive-force controller. — A far more workmanlike and 
effective way than any of these is to make a pulley or collet like 
that shown in Fig. 45, which can be placed on the winding 
square or on the center or hand-setting square, 
and a cord with a weight can be arranged to 
increase or decrease the motive force to any 
desired extent. The two outer circles repre- 
sent the periphery and the bottom of the 
groove for the cord. This pulley has a 
changeable center, which is let through the 
pulley; the fourth circle from the outside 
shows the diameter of the center-piece, the 
third shows the flange on the center, which is 
let into the pulley, and held by two screws, as shown — both 
flange and screw heads being let in level with the surface of the 
pulley. The inner circle and the two fine lines crossing exactly 
at right angles, are to be carefully marked on the metal, as 
guides for getting the central opening perfectly square and at 
the centre of the piece. The corners come at the junctions of the 
lines with the circle. This hole should be exactly in the cen- 
ter, or the force of the weight will not be uniform as the winding 




Fig. 45. 



THE WATCH ADJUSTER'S MANUAL. 279 

square revolves. By having half a dozen sizes of holes, any- 
square can be fitted — the same pulley, cord and weight answer- 
ing for all of the center-pieces. A pulley half an inch in diam- 
eter will be most suitable. A hole is drilled from the bottom of 
the groove diagonally outward, and the outer end cupped to re- 
ceive a knot in the end of the cord, to prevent it pulling through. 

(674.) Use of the cojttroller. — If one of the spring-holding 
tools, such as Fig. 11, is used to hold the movement, a screw- 
post carrying another pulley can be secured in one of the holes, 
5, in Fig. 12, (239.) The cord runs from the controller over 
that pulley, and can carry one or more small lead weights, in 
the same way as the weights of a grocer's scales are changed. 
When placed on a fuzee arbor, if the cord runs in the same 
direction as the chain, it increases the effective motive force and 
makes the arcs larger. By turning it the other way around the 
pulley, it lessens the motive force and makes the vibrations 
smaller. Any desired arc can be obtained and maintained in 
this way. In a going-barrel watch, the pulley must be put on 
the center square, or hand-setting post. 

(675.) Separatijig frictioji errors. — The use of the controller 
enables us to separate the errors due to increased friction from 
the others. For example, if a watch is timed in the horizontal 
position with long arcs, and then timed in the same position 
with short arcs, it will gain in the short arcs; if then tried in 
the vertical (hanging) position with the same short arcs as be- 
fore, it will run just right, (supposing the spring to be practi- 
cally isochronous,) because the additional frictions will cause a 
retardation equal to the gain of the spring. This shows that 
there is a difference of rate with the same arc of vibration, and 
the gaining error of the spring, which would just balance the 
excessive friction of the vertical position, would show itself as 
an error of rate when that friction was absent. By thus lessen- 
ing the arcs (in the horizontal position), without increasing the 
frictions, as above described, we obtain an indication of the 
action of the spring in different arcs. If the rate does not 
change under such circumstances, the spring is (almost) theo- 
retically isochronous (664) ; if it does change, and in such a 
way as to balance the friction errors in the different positions, it 
is practically isochronous. 

(676.) Testing the isochronism. — Let us now take an example. 
The tests are always to be made in a room at the same temper- 
ature (say, about 65° Fahr. ,) because the balance is supposed 
to be not yet compensated, and if the temperature varied, the 
observed rates would contain errors not due to the isochronism 



28o THE WATCH ADJUSTER' S MANUAL. 

but to the variation of the balance by heat and cold. First the 
watch is run dial up for 24 hours, and is found to have gained 6 
seconds; it is then tried pendant up for 12 hours and loses 8 
seconds, and then when tried pendant down 12 hours it loses 
10 seconds. For comparison, we write them thus: 

24 h., dial up, -1~ 6" 

12 h., pendant up, — 8" 

12 h., " down, — 10" 

24 h., 24 h., +6" — 18" = — 24" 

Put the length of trials and the errors in different columns, for 
the long arcs and the short ones. Add the items in the differ- 
ent columns, and compare the totals for the long arcs with 
those for the short arcs. The times are equal, being 24 hours 
for each; but the long arcs gained 6 seconds, while the two 
short arcs lost 18 seconds by the regulator. The short arcs 
were therefore 24 seconds slower than the long ones, and are 
said to have lost 24 seconds. We then alter the isochronal 
action of the spring to make the short arcs gain, and try again, 
with the following result. Dial up (or down) gives the long 
arcs, and the vertical positions give the short arcs. 

(677.) Testing in the quarters. — This time the errors are: — 

24 h., dial up -j- 10" 

12 h., pendant up -|- 6" 

12 h., " down 4- 4" 

24 h., 24 h., +10" + 10" = o" 

The watch is now said to be isochronous, because the rates 
are the same in both the long and short arcs, but there is a 
position error of 2 seconds between pendant up and down. We 
then try in the other two quarters, and the errors are: — 

12 h., pendant right -|- 10" 
12 h., " left - 2" 

showing a position error of 12" between pendant right and left. 
(678,) Correcting the rate. — We first see how we can get the 
rate as nearly alike as possible for the two most important positio7is 
in actual use, pendant up and dial up. For ease of comparison 
we arrange all the rates together, as they would be for 24 hours 
in each position, as follows: — 

24 h., dial up -1- 10" (— i") 

" pendant up +12" (+ i") 

" pendant down -|- 8" (— 3") 

" pendant right -j- 20" (-|- 9") 

" pendant left — 4" (— 15") 



Make the rate slower, — ii" — 11' 



THE WATCH ADJUSTER' S MANUAL. 2S1 

Subtract 11" from each, as that will be half-way between dial 
up and pendant up; then dial up will be i second slow and 
pendant up i second fast, as shown in parentheses after each. 
The other positions will also be improved, with the exception of 
pendant left, which is made worse, as shown by the error in the 
parentheses. To cure that, we can alter the poise of the bal- 
ance to make pendant left 12 seconds faster, (718 to 721,) which 
will also make pendant right 12 seconds slower; pendant right 
will then lose 3 seconds per day and pendant left will also lose 
the same. Every case is different, but by arranging the errors 
as above, a little study will show the best arrangement. In the 
above case we altered the mean-time screws to cause a loss of 
II seconds in the rate. But we might have made pendant up 
just right, by a loss of 12 seconds; then dial up would have lost 
2 seconds, instead of i, as shown. 

(679.) Correcting the isochrofiism — its Ii7?iitatio7is. — The fore- 
going example proves the necessity of close position adjustment 
before isochronizing the spring. It is impossible for the spring 
to correct all errors. All that it can do is to give a certain rate 
(gain or loss) in the long arcs, and another rate in the short 
ones. If that rate balances the errors in a certain position, the 
error in that position will be " corrected," but the errors in other 
positions will not be. Let us consider another example: — 

24 h., dial up -j- 3" 

" pendant up — 5" 

down + 2" 

right - 7" 

left +11" 

(680.) If we regulate the watch to keep correct time pendant 
up, the errors will be as shown in the first column below: 

Dial up -f 8" o" o" o" o" 

Pendant up o" — 8" o" + 4" - 4" 

down + 7"- i"+ 7" + 11"+ 3" 

right - 2" -10"- 1" \- 2"- 6" 

left +16"+ 8" + 16" 4- 20" + 12" 

Instead of that, if we had made the rate correct with dial up, 
the errors would have been as shown in the second column. 
Then suppose we caused the spring to gain 8 seconds in the 
short arcs, the result would be shown in the third column. 
That is as far as we can go with the isochronal adjustment, for 
if we make the short arcs gain any more, say, 4 seconds more, 
the rates would be poorer as seen by the fourth column; and if 
we make them 4 seconds slower the rate would be as in the fifth 



282 THE WATCH ADJUSTER' S MANUAL. 

(68 1.) Tr2ie piu'pose of the isocJwonal adjustmait. — Considera- 
tion of the foregoing details will prove that the common practice 
of adjusting for only two positions is right. That is all that 
the isochronal adjustment can possibly correct. Anything 
more than that belongs to the positional adjustment and should 
be corrected by that. It cannot be done in any other way. It 
is also plain that the practice of adjusting for certain arcs of 
vibratio7i^ (long and short,)' has no proper place in the adjust- 
ment for practical isochronism, (except for investigations as to 
the causes of observed errors,) but that the latter adjustment is 
simply for correcting the errors in the two chosen positions. 
Any positions preferred may be taken, but, of course, the two 
positions in which accuracy is most desirable should be chosen, 
and they are generally pendant up (hanging) and dial up or 
lying down. Such an adjustment relates to actual conditions, 
and is therefore practical. Anything beyond that is not so. 

(682.) In adjusting inarine chrono?neters, which are always kept 
in the same position, the common practice is to let down the 
mainspring to reduce the arcs from i^ turns down to from f to 
|- turn, and time the instrument for the same length of time as 
with the long arcs; if the rate is absolutely the same in the 
long and the short arcs it is called isochronous, on the suppo- 
sition that the short arcs so obtained will be equivalent to the 
short arcs caused by the thickening of the oil after two or three 
years' service. Any intelligent adjuster must see that this is 
entirely wrong. The conditions of actual use are, a slight de- 
crease of motive force, due to thickening of the oil on the 
pivots of the train, and a great increase of friction from the 
thickening of the oil on the balance pivots. The artificial con- 
ditions produced to imitate the actual ones are, a large decrease 
in the motive force, and no increase in the frictions, a very 
different state of things. If a spring was practically isochro- 
nous, it would gain from 3 to 10 seconds in 24 hours when tested 
in the short arcs in that way; on the other hand, if it is adjusted 
so that it will give the same rate on the long and short arcs so 
produced, when exposed to actual conditions it will lose 3 to 10 
seconds more than if it had not been adjusted., on account of the 
thickening of the oil. Turning it up into the vertical position 
will not duplicate the actual conditions, because there is no 
certainty that the side friction would be equal to that of the oil, 
but especially because the rate would then also contain the errors 
due to lack of poise, roundness of pivots or holes, improper sizes, 
and close or loose fitting, etc., etc. 

(683.) The realistic and practical methods of adjusting. — The 



THE WATCH ADJUSTER' S MANUAL. 283 

" realistic" method of imitating the natural conditions, would be 
to slightly weaken the motive force, and put thick oil on the 
balance pivots, then adjust the short arcs. But there would be 
no certainty that the effect so produced might not be too great 
or too small. We can therefore only follow what we may call 
the practical method. If we know by experience how much 
such instruments lose, on an average, we can adjust our spring 
to gain that amount in the short arcs, when tested in the hori- 
zontal position, with the short arcs produced by letting down 
the mainspring or by the controller. Even that is va^xktXy guess- 
ing what the loss would be at the end of two or three years, but 
it is the best we can do, and is far better than the usual method. 
The short arcs should then be the same that they usually are 
after the chronometer has been in use two or three years, and 
they should gain on the long arcs to the amount before stated. 

(684.) In adjusting a going-barrel watch, the long arcs should 
be timed in the horizontal position, with the mainspring wound 
entirely up, and re-wound every 4 hours, to keep it up; the 
short arcs should be in the vertical (pendant up) position, with 
the mainspring wound only i turn, and re-wound every 4 hours 
to the same extent as before, /.<?., to keep it wound i turn dur- 
ing the trial. During the short arcs it should give the same 
rate as in the long ones, as keeping the arcs small all the time, 
in the manner described, will practically equal the future thick- 
ening of the oil. In adjusting a fuzee watch, take the horizon- 
tal position for the long arcs, and the vertical (pendant up) 
position for the short ones, either letting down the mainspring 
or using the controller to make them \ turn smaller than the 
long ones, and make them gain on the long ones from 3 to 5 
seconds per day. As pocket watches are cleaned more often 
than chronometers, this will be ample to cover the thickening 
of the oil, etc. In ordinary watches, no such allowance is 
made, but the long and the short arcs (so produced) are made 
to give the same rate. 

(685.) The adjustnie7it difficult. — The workm.an may think that 
it is a good deal of trouble to isochronize a spring. Well, it is 
some trouble to do a good job. But nothing really good is to, 
be had without trouble. But it is not so hard as it might seem 
at first, from the number of details given. I have endeavored 
to touch every point important to know, have even occasionally 
repeated directions in different ways, have used ungrammatical 
and unscientific expressions, have been diffuse and redundant 
in style, from a desire to make sure that my meanings should be 
noticed and clearly understood by all. But when once compre- 



284 THE WATCH ADJUSTER' S MANUAL. 

hended and become familiar, when the principles or models 
which are to be copied are fixed in the mind, the numerous de- 
tails I have found it necessary to explain and dwell upon will 
become matter-of-course, and the practical work simple and 
easy, so that we may hope for an improvement in the manner 
of treating springs which seems to prevail at present with many 
makers. Judging from their work, a good share of workmen 
now merely try the spring by some "quick test," (524 to 526,) 
and let it go at that. But from what has been said, it will be 
seen that it is little better than a barefaced swindle to pass off 
such a spring as isochronal, for a spring may stand that test or 
even a severer one, and yet not be adjusted for isochronism at 
all. One has no more moral right to call such a spring iso- 
chronal than he has to represent a chain as gold because it has 
a few grains of that metal in it or on it. 

(686.) Practice required. — I have now given all directions 
necessary for selecting and fitting hair springs in the very best 
manner, and making all adjustments required even in the finest 
watches or chronometers. It is not to be expected that the 
workman will observe all the niceties explained, in common 
watches or on low-priced jobs. But if he understands fully 
what has been said in these articles, and uses a reasonable 
amount of thought and judgment in applying it in practice, he 
can, with little or no loss of time, do even his common jobs in a 
manner approximating correctness, and which will not only 
please his customers, but satisfy other workmen, into whose 
hands they may come, that he understood his business. Above 
all will be the satisfaction to himself of working from knowl- 
edge, instead of blind groping and guess-work — and the ability 
to judge whether work is properly done or not. In order to 
get the most benefit from his knowledge — to both learn and 
improve — he should put it into practice at every opportunity, 
even if it involves extra trouble or doing a little more than he 
gets paid for. He will be amply rewarded by his improvement 
in information and dexterity. But without practice his knowl- 
edge will be both useless and fleeting. 

(687.) Rating sheets for isocJirojiizing. — The workman should 
keep a regular record of all his trials, rates, alterations made, 
and, in general, everything which is done in connection with 
the job, and which would be necessary for another man to know 
if he should have to take up the job and finish it. He must not 
imagine that keeping such a record is a mere matter of form, or 
even convenience. It is a legal necessity. The law requires 
every man to keep proper books showing the details of his busi- 



THE WATCH ADJUSTER'S MANUAL. 285 

ness, and to produce them as proof of the truth and justice of 
any claims he may seek to enforce in the courts. If an adjuster 
should have occasion to sue for the collection of pay for his 
work, he would probably be unable to give legal proof of what 
he had done, unless he could produce some systematic record, 
such as is given on the next page. 

(688.) The law of evidc7ice. — In such suits, the first and origi- 
nal entries of what was done, made at the time, are always 
called for, and in some cases no other entries or books will be 
accepted as conclusive proof. The workman must be able to 
swear that he made those precise entries, just as they stand, at 
the time they purport to have been made, and that they were 
and are correct. Otherwise, he could only swear that he believes 
them to be true, but could not swear positively, and he believes 
that he did work about as stated in the entries — while the other 
party could bring other adjusters to say that they had examined 
the watch and that they did not believe any such work, or work to 
that value, had been done, etc., etc., — which would imply that 
his claim for services was not an honest one. It is therefore 
not only a question of doing business in a proper and business- 
like way, but may also involve his reputation as an honest 
business man, as well as affect the collection of money due him 
for work performed. These remarks, of course, apply with 
equal force to the other adjustments, and I have given speci- 
mens of suitable records for each case. 

(689.) Jsochronisfn record. — [See page 286.] 

(690.) Explanatio7i of the rating sheet. — This can be easily 
ruled off as shown, and gives opportunity to make an entry for 
every detail useful for reference in perfecting the work, aside 
from its legal value. The entries are not in connected form, 
as they would be in a real case, but merely to show the different 
details which might occur in different cases. The usual course 
is merely to note the rates in the long and the short arcs. But 
it is obvious that that leaves all the most important points to 
the memory. In other words, such a record is legally no record 
at all. And it is of little or no assistance to the workman him- 
self in trying to recall details of what he had done, the effect, etc. 
The record should show, for each trial, the position, the motive 
force, the arc of vibration, the length of trial, and the actual 
error observed. For the short arc trials, the way the short arcs 
were obtained should be stated — for different ways will produce 
very different results. The last column states any other point 
of interest or useful to remember. The entries for the short 
arcs are not inserted, but are made like those for the long arcs. 



286 



THE WATCH ADJUSTER' S MANUAL. 



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THE WATCH ADJUSTER'S MANUAL. 287 

(691.) Making the entities. — The abbreviations are simple: / 
means pendant; d is dial; a figure shows what hour on the dial 
was up; any position in that column means up, except one: pd 
means pendant down. In the winding column up means wound 
entirely up; -|-, is wound half-way up; i /means wound up one 
turn from the bottom of the fuzee; or, in a going-barrel watch, 
I turn from the point where the stop works prevent the spring 
from running further down. If the stop works are gone, it 
means i turn of the barrel arbor from the position reached after 
running 24 hours. The arc of vibration may be expressed in 
turns, as ij, i, J, etc., or more closely in degrees, which means 
the vibration from one extreme to the other. In expressing the 
rate, ih id ii'\ would mean i hour, 10 minutes, and 11 sec- 
onds; 4" signifies a gain, and — means a loss. The entries in 
the last column mean that we changed the mean-time screws in 
the balance to make the rate 11 seconds slower; that we set the 
hair spring towards the III on the dial ; that we made the top of 
the balance heavier than the bottom for the position XII up, 
etc. If you are particular to keep such records in the manner 
described, they will not only be useful for the purposes already 
stated, but will be a mine of valuable information to you, in 
case you wish to investigate any point, and a pleasure for you 
to look them over. 



PART SEVENTH. 
THE ADJUSTMENT FOR POSITIONS. 



CHAPTER XXXVII. 

Position Faults. 

(692.) Adjustment for different positions should, theoretically, 
be unnecessary, because a watch made on correct principles, 
and well executed, would already be as perfect as it could be, 
and would therefore give as close a rate in the different positions 
as it could be made to do. But in practice there are many 
shortcomings, both in designing and executing the mechanism, 
and in consequence both the amplitude of the vibrations and the 
rate are more or less irregular when the position is changed 
from hanging to lying, or to the different vertical positions. The 
object of the position adjustment is to discover the causes of 
these errors, and correct them, wholly or partially, according to 
the quality of the watch, or of the job. 

(693.) Positio7i variatio7is of rate 2iX& Aw^ to the total amount 
of frictions and other resistances being different in the different 
positions, affecting the movement of the balance and the time 
kept by the watch. It is generally supposed that the causes of 
these resistances and frictions are merely errors in the shapes or 
sizes of the balance pivots or in the poise, and that correcting 
the poise and changing the pivots will remove the errors. But, 
in reality, the causes are very numerous and diverse. They 
may be divided into several classes, as: position errors; rotating 
or varying errors ; escapement errors; errors of proportion or 
design. 

(694.) Class first. — Position errors^ properly so called, are 
those due to a change in the position of the watch, and they do 
not change while that position remains the same. Among 
others, the following faults of that class may be mentioned: 

I. The weight of the balance and its fixed attachments, such as 



THE WATCH ADJUSTER' S MANUAL. 289 

the rollers, hair-spring collet, etc., even when perfectly poised, 
causes a difference in the friction, between the horizontal and 
vertical positions. But as this weight cannot be changed to 
equalize the frictions, we can only accomplish that by modify- 
ing the size of the pivots, or by altering the jewels, etc., as 
hereafter explained. In case the weight of the balance is not 
correct, we can then change it to a correct proportion, as stated 
in the section devoted to the fourth class of errors. 

2. The weight of the central coils of the hair spring rests on the 
balance axis, the same as that of the balance itself. How much 
of its weight is supported by the stud and how much rests on the 
balance staff, it is impossible to say. In the horizontal position, 
probably all but the last coil or half coil is supported by the 
balance pivot, if the spring is so pinned in the stud that it stands 
perfectly free, as was directed in Chapter XVIII, on Fitting 
Hair Springs. But by pinning it a little low in the stud, the 
whole weight of the spring comes on the end of the pivot, and 
exerts an additional mechanical pressure downward, besides, — 
which increases the friction on the pivot. The same effect is 
produced by raising the collet up on the staff. If the watch is 
then reversed so that the balance rests on the other end of the 
staff, there will obviously be less friction on that end, because, 
not only is the weight of the spring supported by the stud, but 
it exerts an upward pressure, tending to lift the balance off the 
pivot. In ordinary watches, the weight of the spring is so small 
that it would not count much as affecting the amount of friction 
on the pivot ends, but the mechanical pressure described might 
be a very effective means of increasing the horizontal friction, 
and so equalizing the horizontal and vertical frictions. But it 
must not be carried so far as to affect its isochronal action — and 
the latter should be tested when this procedure is followed. 

3, The weight of the spring i?t the vertical position. — A similar 
method of varying the weight and the attendant frictions is 
often adopted in the vertical positions, by so shaping the outer 
coil that the stud will support nearly the whole weight of the 
spring in any desired vertical position. For example, if the 
spring shown in Fig. 25, (296,) is pinned perfectly free in the 
stud, and then held in the different vertical positions, a little 
more of. the spring will rest on the balance staff when held stud 
up than with stud down — probably enough more to compensate 
for the greater weight of the outer halves of the coils, (295); 
and the same is true when held stud right, or stud left. So 
that, practically speaking, the weight of the spring resting on 
the staff will be equal in the different vertical positions, if 

19 



290 THE WATCH ADJUSTERS MANUAL. 

pinned in the stud so as to stand perfectly free. But if it is 
desired to take the weight off the pivots in one position, say, 
stud up, and increase the weight with the stud down, the outer 
coil is bent inward a little at r, throwing it towards the stud. 
The whole weight, and a pressure besides, will then rest on the 
pivots when the stud is down. To lessen the weight when the 
stud is at the right, the spring is bent inward between c and d. 

4. Side pressure of the hair spring. — With a tolerably stiff 
spring, this method can produce many times more effect by the 
pressure than the weight alone could do. Whenever there is too 
much friction in any vertical position, see if the spring is out of 
center and is exerting a side pressure in that direction. If so, 
correct the excentricity, or make it excentric in the opposite 
direction. The rule is, to shift the center towards the dial 
figure which is uppermost when the friction is greatest. If the 
greatest error is with XII up, the outer coil is bent to throw the 
center towards the XII, and it will tend to lift the balance 
whenever the XII is up. The bending is done outside of the 
regulator pins, but if the effect should be to change its position 
between the pins, the stud should be slightly turned to restore 
it to the correct position between the pins. If the stud cannot 
be turned, bend the spring at the stud. But as observed in the 
second paragraph, this procedure should not be allowed to go 
so far as to injure the isochronal action of the spring, for that 
is more important than the position adjustment, and the latter 
can be changed in other ways, which are less objectionable. 

5. Escape7?ie7it frictions may vary in the different positions. 
The most common cause is the balance pivots being too loosely 
fitted in the jewel holes, so that the balance and its attachments 
work more deeply when it falls towards the rest of the escape- 
ment than when it falls from them. If this fault is serious, it 
should be corrected, as there is no other way of neutralizing the 
effects. If not too serious, setting the hair spring excentric, as 
directed in paragraph 4, may hide the error. 

6. Lever not poised. — In lever watches, if the lever is not 
poised, it will require a greater expenditure of the energy of the 
balance to lift its weight in one position, than to merely unlock 
it in the opposite position and let it drop by its own weight. 
The remedy for this is obvious. 

7. Difference of friction on sides a7id ends of pivots. — The differ- 
ence of friction on the sides or on the ends of the pivots is a 
very difficult fault to overcome. We know that in nearly all 
watches the balance has a larger motion, or longer vibration, in 
a horizontal position than when it is in a vertical position, or 



THE WATCH ADJUSTER' S MANUAL. 291 

with its edge up. This is caused by a greater friction on the 
balance pivots in the latter case. The adjustment to positions 
is effected by equalizing the frictions, so that the hair spring 
will be able to move the balance through the same arc in any 
position in which it may be held. Even when the pivots and 
jewel holes are correctly formed and finished, the friction on the 
sides may be much greater than on the ends and produce a seri- 
ous difference in the rate between the horizontal and vertical 
positions. If the size and condition of the pivots are correct, 
we can flatten the ends, not so much to increase the surface in 
contact with the end-stones as to increase the distance of 
the contact from the center of the pivot. If the end friction 
could all take place at the outer edge, the radius of friction 
would be practically the same on the ends as on the sides of 
the pivots. To secure that, many workmen not only make 
the ends perfectly flat to the edge, but it has even then been 
proposed to hollow out the center, so that it could only touch 
the end-stone at the outer edge. But that is rather difficult to 
do. 

8. Increasing the end friction, — The end friction can be in- 
creased in different ways. But the only one which is worthy of 
consideration is to slightly incline the end-stone, so that the end 
of the pivot only rests on it at its extreme edge. This unques- 
tionably does increase the friction, but it is liable to wear off 
the end of the pivot around its edge, unless it is burnished very 
hard and the end-stone very highly polished. But it produces 
a still greater effect by the side friction which results from the 
pivot sliding down the inclined surface and being forced against 
the side of the jewel hole. This is only allowable when the 
hole is perfectly polished and the side of the pivot is hard bur- 
nished. The inclination of the end-stone should not be too 
great, or it may cause a much greater error than the end friction 
did. Besides, it is a cardinal rule that in all cases the equaliz- 
ing of the frictions is to be done by lesse?ii?ig the greater ones — 
never increasing frictions unless that is unavoidable. On the 
other hand, when there is an error in the rate, or a lack of 
proper vibration, in the horizontal position, see if the fault is 
not an end-stone that is inclined, instead of being vertical to the 
pivot and giving it a level and easy support. 

9. Lessening the end friction. — When the side friction is very 
much greater than the end friction, the ends of the balance 
pivots may be round, or, at least, not flat. The remedy, of 
course, is to flatten the ends, either perfectly flat, or as nearly 
so as may be found necessary on trial, till the balance will keep 



292 THE WATCH ADJUSTER' S MANUAL. 

Up about the same motion in both the horizontal and vertical 
positions. 

10. Excessive end friction may be due to jewel holes being too 
thick, or pivot too short, or end-stone too far from the hole 
jewel, whereby the shoulder of the balance pivot rubs the jewel. 

11. Another cause is the cup in the jewel being too small and 
deep, containing too much oil, and clogs or retards the shoulder 
of the pivot. Or the oil may be too thick or viscid, or dirty. 

12. Excessive side friction is also caused by jewel holes too 
thick, so that the rubbing surfaces are too great, and the ad- 
hesion of the oil between the hole and the pivot causes a retard- 
ing effect. As a general rule, the length of the hole should 
equal the diameter. If the jewel holes are not perfectly polished 
the error produced is still greater. Holes which are too long 
can be chamfered or rounded out at the ends, to shorten the 
rubbing surfaces. 

13. The side friction of large pivots will cause slowness in the 
vertical positions. The friction increases with the size of the 
pivot, and very rapidly when the pivot is too closely fitted in 
the hole. In such a case reducing the size of the pivots, and at 
the same time giving it more freedom in the hole, will greatly 
lessen the side friction, increase the arcs and make the short arcs 
faster. 

14. If the pivot holes are not round tho. pivot may fall into the 
narrow side, and pinch, when in one of the vertical positions, 
causing excessive side friction, and retarding the balance or 
almost stopping it. The same effect may be produced if the 
jewel hole is chipped on one side, and the edges dig into the 
side of the pivot as it revolves, or cause excessive friction and 
error. When in the opposite vertical position the pivot may be 
perfectly free, thus causing a difference of friction and rate in 
the different vertical positions, and also a difference between the 
vertical and horizontal positions. 

15. Poor aligfiment of Jewel holes. — If the jewel holes are not 
in line with each other, or even if one hole is in line with the 
balance axis while the other is not, the holes (or the one of 
them which was out of line) would be equivalent to oval jewel 
holes, as will be seen by Fig. 46, where the right and left circles^ 
represent the two ends of the hole, as seen with the eye in line 
with the balance axis, and their intersection shows the oval 
opening left free for the pivot, which is drawn with shaded lines. 
If the watch is held in such a position that the oval opening is ver- 
tical, as shown, the pivot will pinch in the hole, all the time ; when 
the oval opening is horizontal, the pivot will wabble about loosely 




THE WATCH ADJUSTERS MANUAL. 293 

in the hole. This action may assist in detecting the error, for 
if the pivot is very loose in one direction and tight in the trans- 
verse direction, while the hole is seen to be round when exam- 
ined with a powerful glass, we may infer that the jewel holes 
are out of alignment. There would seem to be no remedy but 
to fit in other jewels and set them properly. If the error is 
caused by one of the holes not being vertically over the other, 
it will be shown by the balance not being level with the plate. 
If level, hold the movement inclining down- 
ward from you, so that the balance pivots 
fall into the further sides of the holes, and 
gently press on the top of the rim (part near- 
est to you) with a stiff bristle. If loose, then 
press on the sides and it will be tight — or 
both will be the reverse of the above. When- 
ever you take a watch apart, test the align- 
ment of the balance holes (with the end stones off) by putting 
a round broach in them. If the broach is not vertical to the 
plate, or cock, the hole is out of level. Do not put the broach 
in too tightly, or you will crack the jewel in getting it out. 

16. If the jewel holes are too thin^ so that the pivots have too 
little surface to rest upon in the vertical positions, the oil will 
be forced out from between them, and leave the pivot to run on 
a dry surface, causing greater side friction and variations of 
rate between the vertical and horizontal positions. This is 
more noticeable when the balance is heavy. 

17. A inagnet near the watch will attract the balance and the 
lever, the attraction being greatest at the ends of the center-bar 
and the lever. When the position of the watch is changed, the 
direction of the magnetic attraction will be changed relatively 
to the lever and balance, thus producing different effects in 
different positions, and causing very serious errors of rate, 
almost stopping the watch if the attraction is strong, 

18. Iiiequalities. — When the balance pivots are not of the same 
size, or the jewel holes not of the same thickness or shape, the 
pivots differently formed on the ends, or differently fitted in 
their holes, the total frictions will be different in the different 
positions, causing a difference of rate when the positions are 
changed. 

19. Horizontal frictions of pivots unequal. — This may be due to 
one pivot being shorter, (or end stone further away,) or one 
jewel hole too thick, causing the shoulder of the pivot to graze 
the jewel, or clog in the oil. If so, the remedy is obvious. 
Sometimes one end-stone is poorly polished; or too soft, and 



294 THE WA TCH ADJUSTERS MANUAL. 

the end of the pivot wears it. Occasionally, a pivot has been 
dressed down with diamond dust, emery or diamantine, and 
particles of it are imbedded in the steel, making it a veritable 
drill. In such cases, the end should be scraped with a sharp 
graver, held so that the edge cuts and will lift the particles out 
of the metal, not rub over them and press them further in; then 
finish hard with a pivot burnisher. If the pivot is long enough 
to bear it, turning off the surface of the end in the lathe is still 
better. 

20. End frictiotis unequal. — When unequal horizontal frictions 
are due to a difference in the ends of the pivots, they are equal- 
ized by making the ends of the balance pivots equally flat and 
well polished. The extent of the vibrations can be readily ob- 
served when the dial is upwards, by setting the movement holder 
upon a piece of looking-glass on the bench. The balance and 
works can even be examined with the eye-glass while in that 
position, by looking from one side at such an angle that its 
image will be reflected into the glass. This is much better than 
holding the movement above one's head in order to see its under 
side, insures a true and equal horizontal position each time, and 
obviates the trembling of the hand while holding it, which in- 
terferes with the motion of the balance — and is, besides, easier 
and safer. 

21. Side frictiotis less thati end frictions. — If the vibrations are 
greater m the vertical than in the horizontal position, and the 
fault is known to be in the pivots, the end friction being too 
great, we slightly round off the end of the pivots to increase the 
arc in the horizontal position to an equal extent. These changes 
of the shape of the pivots should be done in a lathe, and very 
slowly and cautiously, lest we do too much. The best tool is a 
pivot burnisher, as that both polishes and hardens the surface. 
If a stone or lap is used, the burnisher should finish the job. 
In rounding off the end, the departure from a perfect flatness 
on the end of the pivot should be only sufficient to prevent 
actual contact with the end-stone, so that the rounding off shall 
be barely perceptible to the eye. First remove a narrow ring 
around the outer edge and try. If not enough, take off a little 
nearer to the center of the pivot. If too much is taken off, we 
shall have to flatten the end again, which will shorten the pivot. 
Therefore we take off but little at a time, and as equally as pos- 
sible off each pivot. Always remove any " feather-edge" that 
may appear at the corners of the pivots, with an oil-stone slip. 

(695. ) Class second. — Rotating or varying faults are those which 
vary while the watch is stationary, such as lack of poise, pivots 



THE WA TCH ADJUSTER'S MANUAL. 295 

not round, and the like. In a fine watch, and a good job, all 
such errors should of course be corrected; but very often they 
are either intentionally caused or intentionally left so, for the 
purpose of balancing or neutralizing some worse error. If we 
take a common-sense view of the situation, it is better to have 
every part in the watch out of poise and get a fair rate, than to 
have everything perfectly poised and have a poor rate. What 
we are after is a good running rate, not perfection in the poise, 
or in any other condition. If perfect poise (or anything else) 
will give us the best rate, we make it perfect ; if imperfect poise 
will do that, we make it imperfect. We look at the results, not 
methods. Right or wrong, that is business, and we are doing 
what we are paid to do. But when everything is ordered to be 
made perfect, we of course do that. The following are the 
principal faults of this class: — 

1. Defective poise of the balance and its fixed attachments^ the 
rollers, the hair-spring collet, and the inner end of the hair 
spring reaching to the regular spiral or cylindrical portion. 
The subject of poise is fully treated in Chapter XIX. 

2. Excentricity of the balance. — If the balance is not riveted 
concentrically on the staff, or the staff pivots are bent, or one 
or both of the balance segments are bent out of the true circular 
form, (at mean temperature,) or any similar error exists, it will 
cause the same effect as lack of poise or as pivots not round 
(No. 4.) This can generally be detected by testing the balance 
in the calipers to see if the rim is perfectly concentric with the 
axis. 

3. Hair spring out of poise. — This fault can be detected in the 
same way as the last one, if the spring is cylindrical. Test it 
with the balance staff vertical. With a flat spiral spring, see if 
the coils rise regularly from the center as the balance is gently 
whirled around in the calipers (277). The spring should always 
be concentric at the center, although it is sometimes made ex- 
centric at the outside. (See (694), No. 3.) 

4. Pivots not round. — The effect of the pivots being oval, 
three-sided, flattened on one side, or otherwise varying from a 
true cylindrical form is shown by Figs. 47, 48, 49, in which the 
circles represent the jewel holes, and the interior ovals are the 
pivots. In Fig. 47, the pivot is so well fitted in the hole that it 
does not fall so far below the center as in Fig. 48, but the effect 
is just as bad, for the nearer vertical the side contacts are, the 
more the pivot will wedge and pinch in the hole, clogging or al- 
most stopping the motion. In Fig. 48, the pivot does not pinch 
so much, but it lets the balance down further, the distance of 



296 THE WATCH ADJUSTER' S MANUAL. 

the fall being shown by the two dots. In vibrating a quarter 
of a turn, to the position of Fig. 49, the entire weight of the 
balance has to be lifted, by the pivot, as shown by the dots, 
the lower one being the axis of the balance as in Fig. 48, and the 
upper one is the distance it has been lifted when in the position 
shown in Fig. 49. This of course implies heavy friction, and a 
great expenditure of the momentum of the balance in overcom- 
ing it. In every vibration of i^ or \\ turns, this lifting occurs 
three times, and the pinching occurs three times, so that it really 
is a worse fault than a lack of poise, and is much more frequent. 
The heavy pressure also forces away the oil, and the pivots 
virtually run dry. 

Of course, pivots are never so much out of shape as has been 
shown in the cuts for the sake of clearness, but the principle is 
the same, and even when the pivot is but little out of round, 
barely enough to re??iove the supporting part underneath^ the effect 
is as great as if the whole under third of the pivot was gone. 
Although but little is thought about this fault, there can hardly 
be a doubt that it (including No. 5, below, and No. 15 in class 






Fig. 47. Fig. 4S. Fig. 49. 

I,) is the cause of a large share of the excessive frictions in 
vertical positions and of position errors of rate. Detecting the 
error, when slight, is difficult, (715.) The best way is probably 
to whirl the balance in the calipers, watching the pivots with a 
strong glass. There is only one remedy for the jobber, and 
that is to center the stdiH perfectly in the lathe and turn the pivot 
off true, (removing as little metal as possible,) almost finishing 
it with the graver, then burnish it hard while running at high 
speed. In the factories, the pivot could be ground true, both 
wheel and pivot revolving in opposite directions at high speeds. 
5. Bent piiwts; poor alig7wient of pivots. — When a pivot is bent 
in a certain direction, it is mechanically oval, or spread out in 
that direction, as shown in Figs. 47, 48 and 49, and its action 
in the hole is the same as above described for an oval pivot. If 
one pivot is not in line with the other, one or both of them will 
act in the hole as before described, being virtually oval. This 
will be evident from Fig. 50. If the eye is directly in line with 




THE WATCH ADJUSTER' S MANUAL. 297 

the axis of the staff, and the right-hand circle shows the outline 
of the pivot at the shoulder, and the left circle is its outline at 
the end, it will be mechanically equivalent to the pivot shown 
in Fig. 47, and the friction and error of rate will be as there 
described. 

The remedy is the same as for that, except when the pivot is 
bent, in which case it should be straightened. A pivot out of 
line can be bent to bring it into line with the 
other, but then it will probably also require a 
smaller jewel hole. This shows the necessity of 
care in turning pivots. In turning the first 
pivot, the other end of the staff should have a 
well formed and conical point, and be perfectly Fig. 50. 

centered till the outer end is finished truly. 
When reversed, this pivot should be perfectly centered while 
the other pivot is being turned. Both pivots should be either 
turned or ground so that nothing is required to finish them 
except a hard burnishing, which should be done while the pivot 
revolves at high speed. 

6. Magnetized balance. — A magnetized balance has its North 
and South poles, and is attracted by every piece of iron or steel 
near it, whether in or out of the watch. This alternately at- 
tracts and repels it, producing such irregular vibrations that 
rating the watch is out of the question until the fault is removed. 
For the method of detecting and removing magnetism see 
Chapter IV. 

(696.) Class third. — Escapement errors are fully considered in 
special articles. See Chapter XXV for the cylinder escapement. 
Chapter XXVI for the duplex, Chapter XXVII for the lever, 
and Chapter XXVIII for chronometers. 

(697.) Class fourth. — Errors of proportion or design include 
faults in the design or proportions of the different parts, gen- 
erally the fault of the maker. Among those which affect the 
timing in positions are: — 

1. Balajice too heazy. — It is well known that a heavy balance 
causes great errors between the horizontal and vertical positions, 
and if much too heavy correct timing in positions is impossible. 
The method of testing the proper weight of the balance is given 
in Chapter X, sections (141) and (142.) 

2. Motive force co7isidcrably too great for the balance. — It is well 
known that if this is the case, the watch will be difficult or im- 
possible to time in positions. The only method of testing this 
point open to the jobber is first to ascertain as above if the bal- 
ance is too heavy (in proportion to the balance spring) to admit 



298 THE WATCH ADJUSTER'S MANUAL. 

of getting the same rate in the two positions, (horizontal and 
hanging,) and if not, then weaken the motive force in any con- 
venient way, as widely as possible, to find a strength which 
gives but little difference of rate in the two positions, even when 
the strength is varied within the limits which are unavoidable 
with the going-barrel. 

3. Train too quick. — In watches with very quick trains, (19,- 
000 to 21,000 beats per hour, and upward,) there will be a loss 
in the hanging or vertical positions, as compared with the hori- 
zontal position, which is very difficult to overcome. See No. 4. 

4. Balance too light. — In this case, also, the above error is 
found, and is thought to be due to the frictions in the vertical 
positions being too great in proportion to the weight of the bal- 
ance. If the watch is free from the faults before stated, espe- 
cially pivots or holes out of round or out of alignment, there 
would seem to be no remedy except to make the balance pivots 
smaller, and fit new jewel holes, or else shorten up the hair 
spring to quicken the vibrations in the vertical position. This 
fault is especially noticeable in very small watches, and the 
spring sometimes has to be shortened up as much as two turns, 
to produce the desired effect. 

5. Hair sprijig too long., causing a loss in the vertical positions. 
This is practically the same as the previous one. 

6. Bala7ice pivots too closely fitted is sometimes the cause of the 
watch losing in the vertical positions. In such cases, making 
them very slightly smaller by burnishing will enlarge and quicken 
the short arcs and remedy the error. 

7. Fourth and escape wheels too heavy., adding to the frictions, 
making the escapement sluggish, diminishing and retarding the 
impulse, and causing a loss in the vertical positions. 



CHAPTER XXXVIII. 

Adjusting for Positions. 

(698.) Order of the adjustments. — The usual order is to test 
the isochronism first, then regulate closely to time at mean 
temperature, adjust for heat and cold, then for positions, first 
at mean temperature, and afterwards in heat and cold, again 
poise the balance, if needed, then rate as closely as possible. 
That will do very well, when the adjustment for positions is 
only attended to as far as may be required to detect some glar- 
ing fault of poise or fitting. The position adjustment is gener- 
ally treated as a very small and unimportant matter. In ordinary 



THE WATCH ADJUSTER'S MANUAL. 



299 



watches, it is not done at all, and even in good watches most 
workmen adjust only very slightly, for hanging and dial up. 
But the foregoing list of position errors shows that it is a matter 
of the very highest importance, and, if properly attended to, 
will improve the condition and performance of the watch as 
much as any other adjustment. Whenever it is to be thoroughly 
done, as it always should be in fine watches, the preferable order 
of adjusting would be: positions, isochronism, compensation. 
But the usual order is isochronism, positions, compensation. 
Also, see section {661,.) 

(699.) Requisites for adjusting. — Supposing that the fitting of 
the hair spring has been done in accordance with the directions 
given, there will be no probability of our 
having to change the spring or the balance 
after adjusting for isochronism, and even 
if we did have to change the spring, it 
could be isochronized without disturbing 
the position adjustment. The watch should 
(after the isochronal adjustment is finished,) 
be closely regulated at mean temperature, 
which must be the same throughout the 
trials. We require a movement holder, by 
which the movement can be held either 
vertically or horizontally, such as shown in 
Fig. 51, in which .S" is a heavy stand or 
base, carrying a table having two clamps, 
/ /, for receiving the edge of the watch or 
movement, the other edge being held by 
another clamp /, which slides on the rod r, 
and is secured by a thumbscrew 71. The 
table, with the rod and watch, turns on a 
joint JV underneath, and is secured in any 
position by thumbscrew. The spring-holding tool, Fig. 11, 
(238,) can also be used for position timing, by securing in the 
holes 55, Fig. 12, four screw posts, whose upper ends are bent 
(L-shaped) outwards as far as the edge of the base A to hold it 
upright when resting on the edge and the points of the screw 
posts. This holds it in any of the vertical positions. Holes 5 
can be put at all the corners, for this purpose. If these posts 
reach up higher than the end of the runner/, the whole tool can 
be inverted and rest on the ends of the posts, thus holding 
the movement in the other horizontal position. We also need 
sheets of paper, with columns ruled for the arcs and the times, 
/>., the gain or loss, in each position, (734). Much of the 




Fig. 51. 



J 



300 THE WATCH ADJUSTER' S MANUAL. 

adjustment, however, will be mechanical tests and observations 
of the arcs, irrespective of timing, if the foregoing directions 
are carefully followed. 

(700. ) The differetit positions of the 7novei7ie?it. — Much confusion 
is caused by different ways of naming the positions, some work- 
men meaning the position of the watch or movement, others 
that of the balance, or that of its staff. The vertical position 
of the staff would be the horizontal position of the balance and 
of the movement. In order to have a definite and invariable 
meaning for every term, let it be understood, once for all, that 
the positions always mean the positions of the watch. When 
"the vertical position" is spoken of, it means the hanging 
position of the watch. But as that does not indicate the position 
of the movement, the figure on the dial which is uppermost 
should also be specified when more than one vertical position is 
considered, i.e.^ call it XII up, or III up, as the case may be. 
The horizontal or lying position is lying down, with the dial 
uppermost, and is often called dial up. The reverse horizontal 
position would be dial down. 

(701.) When the different vertical positions are concerned, 
specify them by the dial figure which is uppermost, as: XII up, 
III up, VI up, IX up. Many workmen express it pendant up, 
pendant down, pendant right, pendant left, but those terms do 
not indicate any particular positions of the movement, for pen- 
dant up may mean XII up or III up, and pendant right may 
mean either XII up. III up, IX up or VI up, according to 
whether the dial or the plate is facing us, or whether it is a 
hunting case or open face watch. If the term pendant is used 
at all, always accompany the first use of the term " pendant up" 
with the dial figure which is then up, thus, "pendant (XII) up," 
which makes the meaning of pendant up definite; and always 
specify the other positions of the pendant with the dial facing 
you. But it is better to go exclusively by the dial figures, or at 
least to use only the term pendant up, as indicating the hanging 
position. 

(702.) The top of the balance. — In expressing the position of 
the balance, it is supposed to be still, and free from any pressure 
tending to rotate it. The watch is in the hanging position. A 
vertical line drawn through the axis of the balance, will touch 
the rim at the top and bottom points. The upper point touched 
by that line is the top of the balance, and the upper half of the 
rim is the upper side of the balance. In the same way, the 
lower point is the bottom, and the adjacent portion of the rim 
is the under side of the balance. 



THE WATCH ADJUSTER' S MANUAL. 301 

(703.) Measuring the vibi-ations. — The mechanical position 
errors are discovered best by observing the exact arc of vibration 
in each trial. To know what the arc is, mark on the plate, 
(with whiting and oil,) just outside of the balance rim, the position 
of some conspicuous point or part of the rim when the balance 
stands freely at rest, (702.) This point may be the cut in the 
rim, some screw, or anything else which can be easily and 
clearly seen at the end of each vibration. Then make another 
mark exactly opposite the first one, /.<?., half a circle from it, 
and two marks just midway between them. These latter will 
be one-quarter of a circle, or 90°, from the former. Now make 
smaller marks midway between the others, and you have marks 
which will be one-eighth of a turn apart. When the balance 
vibration ends at one of these marks, its distance from the first 
or central mark measures one-half of the vibration. Thus, if 
the balance cut or screw stops opposite the third mark, that is 
§ turn from the center, and the balance is vibrating f of a turn; 
if it stops at half the circle from the start, it is i turn; if it 
stops half-way from that mark to the next one, it is i-|- turns, 
and so on. 

(704.) Detecting mechanical position faults by the arcs. — Most of 
them can be detected in the ways already described, and cor- 
rected before the trials by running the watch are commenced. 
Those not so disposed of are detected or tested by running the 
watch in the different positions with the mainspring wound up 
an equal distance for each trial, and noting down the exact arc 
of vibration in each position. It is only necessary to continue 
each trial long enough for the balance to attain its normal 
vibration for those conditions, — two or three minutes being gen- 
erally enough. The mainspring should not be wound entirely 
up, as there is often an extra pull on the spring just after wind- 
ing, and it is better to let it back a quarter or half turn after 
winding, being careful to let it down the same amount each 
time. This precaution is not necessary with a fuzee watch. 
First find the extent of the arcs in the horizontal positions, dial 
down and dial up. If not equal, they should be made so. See 
19 and 20, in section (694). The horizontal arc is the standard 
of comparison for the vertical arcs. The latter are then tested 
in the alternate positions, XII up and VI up, then III up and IX 
up. Each pair of opposite arcs are carefully compared, the 
cause of the difference studied out, and then corrected. 

(7*^5-) Cause of the error. — The balance may be out of poise; 
the balance jewel holes may not be round, not evenly polished 
inside, or too large for the pivot — allowing the balance to fall 



302 THE WATCH ADJUSTER' S MANUAL. 

towards the lever, escape wheel, etc., or away from them, 
and interfere or change the action of the parts — or any one out 
of a score of other faults may cause the trouble. It must be 
remembered that the arcs should be equal in the different positions. 
If they are not, the change of the arcs when held in the differ- 
ent positions will guide us to the cause. Inasmuch as the greater 
the friction is, the smaller the arc will be, we know in which 
position to remedy the inequality of the friction, and we may 
also ascertain the effect of our alterations, by simply noting the 
change in the arcs while the motive force is the same as before. 
It is desirable to equalize the frictions in the different positions 
as nearly as possible, as it leaves less to be accomplished by 
isochronizing the spring, and there is a limit to the amount of 
irregularity which this adjustment can compensate for. Besides, 
the more perfect all the parts of the watch are the finer the per- 
formance which we may hope to obtain from the spring. When- 
ever the error seems to be a lack of poise in the balance or 
hair spring, let it pass for the present, as it may have been 
intentionally put out of poise. But if you are under orders to 
do 2i perfect ]oh, correct it. After you have made all the cor- 
rections you can from the mechanical indications, and got the 
arcs of vibrations as nearly alike as possible in all positions, as 
above, the timing trials may now begin. 

(706.) Ma7ijier of testing. — If it is not known that the isochro- 
nal adjustment is correct, we must make our trials in such a way 
as to eliminate isochronal errors from the result, as far as prac- 
ticable. Otherwise it would be difficult or impossible to tell 
whether the observed variations in the rate were due to position 
faults or to isochronal faults in the spring. If it was known 
that the hair spring alone would give the same rate with differ- 
ent arcs — all being in one position, (665,) then any error in the 
different positions would evidently be due to some faults in the 
escapement, pivots, or other points referred to in sections (694) 
to (697). But inasmuch as we expect the isochronal adjustment 
to correct the error which remains after we have adjusted for 
positions as closely as we can, it is clear that we must conduct 
the position adjustment in such a way as to first discover the 
true nature and the full extejit of all position faults, unhidden, 
unmodified and uncorrected by the spring, so that we can deal 
with them on their own merits. 

(707.) Distinction between the isochronal afid positio?ial adjust- 
ments. — It should be remembered that the object of the positions 
adjustment is (i) to get the arcs equal in the different positions, 
and (2) to get the frictions, position faults, and disturbing in- 



THE WATCH ADJUSTER'S MANUAL. 303 

fluences of all kinds, as small and as nearly equal as possible in 
the different positions. It properly has nothing to do with 
correcting the rates isochronally in order to make them equal 
in the long and short arcs. It deals only with the rates in differ- 
ent /^^///^>^^, 2ismea?ts of detecting position faults, and ascertain- 
ing what effect mechanical alterations have in correcting those 
faults. We are not adjusting or correcting the rates, but the 
mechanical condition of the escapement — and are doing it ex- 
clusively by mechanical alterations. The arcs and the rates are 
merely our guides in the work. 

(708.) The isochronal adjustment, on the contrary, has for its 
objects (i) to get the same rate in long and short arcs, and (2) 
to "correct" position errors, i.e.^ to hide them by the action of 
the spring, which is done by producing an isochronal error just 
equal to, and the reverse of, the position error, which is thus 
balanced, and the rates made "equal or correct." Many of the 
methods of adjustment I have named are found in both adjust- 
ments, because they produce analogous or equivalent effects in 
both. But if those mentioned in the positional adjustment are 
properly carried out there, they will not be needed in the iso- 
chronal adjustment, for they will have already produced all the 
effect and done all the good they can, in the positions adjust- 
ment, and the isochronal adjustment will be narrowed down to 
mere alterations of the springy for correcting the small errors 
which remain. That is as it should be. But I have felt com- 
pelled to specify the remedies applicable in each adjustment, 
from knowing that neither of them may be thoroughly done, 
and the remedies may be needed in either, or in both. 

(709.) The trials by tiining in positions. — Having first tested the 
position faults by observation of the arcs in different positions, 
and corrected them, so far as we could, as 7nechamcal faults.^ we 
must now test the condition of the escapement by tinmig it in 
different positions, and be guided by the errors in the rates. If 
the previous mechanical trials have been thoroughly made, (704, 
705,) there will probably be little left for the timing trials to 
accomplish. But in order to cover all contingencies, I will de- 
scribe the latter as fully as if they were the only ones. We first 
make position trials as directed in section (711), and then poise 
trials as in section (713,) and compare the rates so obtained as 
described in section (714). This comparison of results will 
clearly indicate what the trouble is, and enable us to correct it 
with certainty. It is only necessary to point out here that when 
the pivots are not round, the arc and the rate will be the same 
in the opposite positions, but when the errors are faults of poise 



304 THE WATCH ADJUSTER'S MANUAL. 

or escapement defects, the arcs and rates will both be different 
in the opposite positions. I have described the adjustment by- 
extent of arcs and that by the rates separately, in order to 
make the principles clear, but in practice both the arcs and the 
rates can often be observed at the same time and in the same 
trials. 

(710.) The best arc of vibration. — It is known that when the 
arc is i:^ turns, the watch is least affected by errors in the poise 
of the balance, etc., (also, least affected by magnetism,) and 
the trials designed to discover the position errors, separate 
from the poise errors, should therefore be made with arcs of i^^ 
turns. The poise trials, on the contrary, should be made with 
arcs as far from i^ turns as convenient to obtain, in order that 
the errors of poise may produce their full effect in the rate. It 
is evident that the best arc for running pocket watches would be 
i^ turns, or in the case of going-barrel watches, in which the 
arcs differ when the mainspring is wound up or run down, they 
might vary from i-J- turns down to i turn, the average being i^ 
turns. They will thus be most free from position errors. In 
testi?tg such watches, however, the arcs must be caused to differ 
considerably from i^ turns, because the rate might be very fair 
with that arc, even when the poise was greatly at fault, and 
would yet cause serious errors when running with arcs which 
were smaller. 

(711.) The tifning trials for position errors. — Having the rate 
with pendant up as a standard, you time the watch in the 4 
vertical positions, for 6 hours each, with the motive force the 
same in each trial, and such that the arcs will be as near i:|- 
turns as possible. You thus get the position errors, nearly free 
from errors of poise or isochronism. A loss in any position, as 
compared with the opposite vertical position, indicates greater 
resistances or frictions in the former. The cause is to be sought 
by the indications known to be given by different faults, as fully 
described in the preceding Chapter. 

(712.) Meaning of loss and gain. — The term loss or gain is a 
relative one. There may be a gain in both positions, as com- 
pared with the regulator, but the one which gains the most is 
said to gain on the other. Or there may be a loss in both, 
but the one which loses the most is said to lose on the other, or 
we may reverse it, and say that the latter gains on the former. 
If one loses and the other gains, as compared with the regulator, 
the difference is the stun of both errors, and that is the amount 
by which one gains or loses on the other. 

(713.) Timing trials for errors of poise. — Make another set of 



THE WA TCH ADJUSTER'S MANUAL. 305 

4 trials, similarly to the above, but with a very different arc — 
preferably about f turn, but with the saine motive force in each 
trial. This fully develops the effects of lack of poise in the 
different positions, but is still nearly independent of isochronal 
errors, owing to all the trials being made with nearly the same 
arc. In comparing results, say, with XII up and VI up, (or 
with the two other opposite positions,) if there is a gain with 
XII up, as compared with VI up, it indicates that the top of the 
balance is heavier than the bottom in the latter position, i.e.^ 
supposing the balance to be brought to rest, with VI up, the 
heavy side of the balance is at the top. The rule is that when 
there is a loss in a certain vertical position, (as compared with 
the opposite vertical position,) the top of the balance is heavier 
than the bottom, />. , provided the error is caused by lack of 
poise. This rule is only for arcs of less than i^ turns; over 
that, the error is the reverse of that stated. 

(714.) Comparing position a7id poise errors of rate. — It is now in 
order to study out the causes of the errors of rate and correct 
them. If the position errors observed in the first set of trials, 
in any two opposite positions, are found to be increased in one 
position and also reduced in the other, in the second set, it may 
be inferred that in the latter trials poise errors were added to 
the position errors, and it will be well to test the poise, accord- 
ing to the rule in the preceding section, i.e.., in the position 
where the loss was increased the top of the balance would be 
heavier than the bottom, if the trouble is in the poise. But if 
the second trials do not show any such opposite effects in oppo- 
site positions, as described, when compared with the first set, the 
change may be due to other causes than the poise, which act 
differently with different arcs, and they should be sought out, 
by the indications in Chapter XXXVII, and corrected as far as 
may be. It should be remembered that while the effects pro- 
duced by imperfect poise are reversed in the two opposite 
positions and neutralized or absent in the two transverse 
positions, the errors caused by escapement frictions are very 
similarly disposed, but those due to pivots or holes not round 
are alike in the two opposite positions and reversed in the trans- 
verse positions. As it is easy to test the poise mechanically, 
as well as the roundness of the holes and their alignment, it 
should not be difficult to locate the fault, which should be at 
once corrected. 

(715.) Cause of errors. — To detect the cause of the variations 
between the different vertical positions, we also have the follow- 
ing indications, supposing the balance to be properly poised. 
20 



3o6 THE WA TCH ADJUSTER'S MANUAL. 

As a general rule any increase of friction in the escapeinent tends 
to retard the short arcs more than the long ones. If the trouble 
is in the escapement it will be detected by moving the roller or 
rollers of the lever or chronometer around on the balance staff, 
putting in beat and trying, when the errors will take place in 
the same positions with reference to the roller as before, irre- 
spective of the position of the balance. But if they occur in the 
same positions with reference to the balance as before, then, if 
the balance is in poise, the pivots are not round, and their revo- 
lution causes them to alternately raise the balance and let it 
down, according as the greatest width of the pivot is horizon- 
tally or vertically across the jewel hole. Sometimes moving 
the rollers half-way around on the staff will neutralize the 
errors, if they are not too great. But pivots being sensibly out 
of round is a very serious fault and ought to be corrected. The 
amount of position error that the isochronism can cover is very 
limited, and it should be called upon to hide only those position 
errors which it is found impossible to remove by mechanical 
corrections and adjustments. I will therefore give the mechan- 
ical methods of correcting them. 

(716,) Equalizing the horizontal and vertical positions. — We can 
equalize the arcs and the rates in the horizontal and the vertical 
positions by increasing the frictions in the horizontal positions, 
as described in Chapter XXXVII. Also, see the section (722) 
on setting the hair spring out of center, or changing the length 
of the hair spring or replacing it with a spring of the same 
strength but shorter. See section (697,) No. 5. That will only 
leave the different vertical positions to be equalized. But 
such changes are not advisable unless the error is large. 

(717.) Equalizing the vertical positions. — For doing this, we 
have the following possible courses: changing the poise of the 
balance, setting the hair spring excentrically. Neither of these 
methods should be adopted unless the error is too large to be 
otherwise corrected, as it is very important to have the rate the 
same in the different vertical positions. The other courses open 
to us should have already been carried out before this, if such 
changes were necessary. 

(718.) Rules for changing the poise. — The balance may be in 
perfect poise, but it can be put out of poise to cause a gain or 
loss in a certain position of the watch. If the watch gains in 
one vertical position as compared with the opposite — supposing 
them to be XII up and VI up, — a small amount of metal is re- 
moved from the bottom of the balance, (/.<?., the bottom when 
at rest with XII up,) thus making the top heavier, and causing 



THE WATCH ADJUSTER'S MANUAL. 307 

a falling back or loss in tlie former position. On the other 
hand, if the gain occurs with VI up, the metal is removed from 
that part of the rim which is at the bottom when at rest with 
the VI up, and causes a slight loss of rate in that position. 
Care must be taken not to remove too much. In screw bal- 
ances, turning the screws in corresponds to removing metal, as 
it makes that side virtually lighter. The same effect is pro- 
duced by turning the screws out on the opposite side, as making 
one side heavier is equivalent to making the other side lighter. 
But the screws should be turned in on one side the same dis- 
tance as they are turned out on the other, else the rate will be 
affected. 

(719.) Changing the poise of a co??i-pe?isation balance. — T h e sere ws 
of a compensation balance must not be changed, except the 
timing screws, and they must be moved equally, as just ob- 
served. In the case supposed above, when the watch gained 
with XII up, the balance is brought to a free rest, and the tim- 
ing screw which is then nearest to the XII, i.e.^ at the top, is 
drawn out and the opposite screw turned in, thus virtually 
making the balance heavier on the former side and lighter on 
the latter, at the same time, without affecting the rate. If 
there was a gain in two vertical positions, as with XII up and 
III up, the timing screws nearest to the XII and III are drawn 
out and those nearest to VI and IX turned in equally. The 
rule is, when the balance is at rest, turn out the screw nearest 
the fast position and turn in that nearest the slow position. 
By fast position is meant the position in which the watch 
gained the most; the slow position is that in which it either 
lost, or did not gain so much, compared with the opposite verti- 
cal position. 

(720.) When useless. — This change of poise is not adapted for 
watches which at one time vibrate over i^ turns and afterwards 
fall off and become less than that, but only for those whose arcs 
are always more, or always less, than i^ turns. At and near 
i^ turns, this change produces little or no effect. 

(721.) Timing in reverse. — Above i^ turns the effect is the 
reverse of that above described, consequently, if the poise was 
changed to correct a certain error, the change would be inopera- 
tive at 1^ turns, and would make the error worse when the arc 
was over i^ turns. When the timepiece always vibrates over 
i^ turns, the poise is sometimes altered to secure a loss or gain 
in certain positions, and in such cases the directions already 
given are reversed. Such procedure is known as " timing in 
reverse." 



308 THE WA TCH ADJUSTER'S MANUAL. 

(722.) Rules for setting the spring excentric. — When there is a 
loss in one vertical position, say, XII up, as compared with the 
opposite position, the spring is so bent in the outer coil as to 
carry the center towards the XII. It of course cannot actually 
move in that direction, but it exerts a pressure and forces the 
pivots against the sides of the jewel holes, thus lessening the pivot 
frictions when XII is up, and of course increasing them when 
VI is up. It tends to lift the balance in the former position, 
and presses it down in the latter, adding to the friction as if the 
balance was heavier. It is evident that this could be caused to 
change the frictions similarly in two adjacent positions. If the 
watch loses both with XII up and III up, the spring can be set 
towards the point midway between XII and III on the dial, and 
it will quicken the vibrations in both the positions stated, but 
not so much as if it was bent directly towards one of them, 
because the effect is indirect and divided between them. This 
procedure not only changes the relative amounts of the frictions 
in the vertical positions, but it also increases the frictions in the 
two horizontal positions, and causes a falling off in the arcs and 
a loss in the rates in those positions — an effect which should be 
borne in mind when making such changes. 

(723.) Disadvantages of this method of adjusting for positions. — 
It must also be remembered that setting the spring out of cen- 
ter, if carried too far, will injure the isochronism, and damage 
the watch in all positions, for the sake of a little apparent im- 
provement in one or two. Besides, the effect is not great, and 
can correct only slight errors. In some cases it does not appear 
to correct the error at all, but it probably is just able to neutral- 
ize some error, which would otherwise show itself in the rate. 
Whenever the effect of this procedure is to injure the isochro- 
nism, it must be abandoned, and the spring either restored to 
concentric position or sufficiently so to avoid disturbing the 
isochronism. In pocket watches which are carried so loosely 
that they take all positions in the pocket, neither this method 
nor the change of poise is of any advantage, and may even be 
a disadvantage. Watches which are treated by either method 
should be worn in a closely fitting pocket, with the chain draw- 
ing upon the pendant, to maintain it in that position. 

(724,) Equalizing the vertical and horizontal positions by the length 
of the hair-springy as mentioned in section (716, 697, Nos. 4 and 
5,) comes properly under the head of isochronal adjustment, 
and will be found fully treated there. If that adjustment has 
been accurately made, there will be no need of doing it as a 
part of the adjustment for positions. But if the vertical positions 



THE WATCH ADJUSTER' S MANUAL. 309 

are excessively slow, and no other method seems open for trial, 
the spring can be shortened up, or a shorter spring of the same 
strength substituted. 

(725.) Choice of methods. — In making the mechanical adjust- 
ments, the only course is obviously to correct the faults, what- 
ever they may be; but in subsequently equalizing the arcs or 
correcting by the errors of rate, we have a choice of methods. 
As a general rule, the more usual methods are preferable in the 
following order: — 

(726.) For equalizing the horizontal and vertical positions, 
making the ends of the pivots flat or sloping, to increase the 
horizontal frictions, or round to lessen them; or making the 
pivots smaller or the jewels thinner, or better polished, to lessen 
the vertical frictions. If the jewel holes are too long, instead 
of making the cup deeper or chamfering out the ends of the 
holes, make an extra cup on the back side, next to the end- 
stone. To equalize the horizontal and the pendant-up posi- 
tions, bend the spring towards the pendant. 

(727.) For equalizing the different vertical positions. — If the 
watch is in good condition, there should be little or no differ- 
ence between them. Look for pivots or holes out of round or 
out of alignment; loose pivots causing difference in the action 
of the escapement; change of poise, when it is applicable, 
(720); setting the hair spring excentric; turning the roller and 
other parts on the balance staff (715); etc. 

(728.) Necessity of equalizing the frictions in different positions. — 
It must be repeated that the isochronal adjustment, which is 
usually depended on to counterbalance the errors arising from 
position faults, is able to do so only to a very limited extent; 
consequently, if the position errors are so great that the isochro- 
nal spring is barely able to correct them, or perhaps cannot 
correct them fully, it will not be able to provide for excessively 
large arcs of vibration, such as are constantly caused by carry- 
ing, shaking, etc., nor even for the additional differences due to 
variations in the motive force when the spring is more or less 
wound up. The watch will then run as if the spring was not 
isochronous, when it is really doing all that such a spring can 
do. The trouble is not with the spring, but with the excessive 
position faults. This will show the necessity of following the 
suggestion before made, that the position faults should be 
treated as mechanical defects, and corrected as such, as thor- 
oughly as possible, by equalizing the arcs and the rates in the 
different positions, before calling on the isochronal adjustments 
to finish the work. 



3IO THE WATCH ADJUSTER' S MANUAL. 

(729.) Finishing the adjust7nent. — When we have done that, 
(728,) the adjustment for positions is finished, for that adjust- 
ment properly includes nothing more, as I have already ex- 
plained, (707, 708,) and any further alterations belong to the 
isochronal adjustment. I am perfectly well aware that it is 
customary to alter the isochronal action of the hair spring to 
correct for the remaining errors of rate, and to call that " ad- 
justing for positions," but it is not so. It is adjusting for 
isochronism to hide position errors which the positional adjust- 
ment has failed to remove. Although it is no part of the 
positional adjustment, I will describe the method usually fol- 
lowed, so that the reader may have both the old and new ways 
before him. 

(730.) Correctijig the re??iaining errors. — The trials are con- 
ducted in the same way as trials of the isochronism, i.e.^ by 
comparison of rates in long and short arcs, the mainspring (in a 
going-barrel watch) being wound up the same distance, to get 
the motive force the same in each trial. And in order that they 
may apply to position errors, the rates in the horizontal positions 
are supposed to represent the long arcs, and those in the 
vertical positions correspond to the short arcs. The trials are 
made in two opposite vertical positions for the short arcs, for 12 
hours each, and their variations added together. This rate for 
the short arcs is compared with the rate in the long arcs for 24 
hours, making the times equal. If the two rates are the same, 
for long and short arcs, the spring is said to be isochronous; if 
the rates were also the same in the two vertical positions, the 
watch is also adjusted for those positions; but if those rates 
differ, there is still a position error. The other two opposite 
positions are tested in the same way. If the position errors are 
small, the watch is already practically adjusted for positions. 
But supposing that they are still large, what shall we do ? The 
isochronal adjustment is absolutely useless in such a case. As 
stated in section (661,) it can only be adjusted for two positions, 
at the most. Whether we like it or not, we shall be compelled 
to return to the positional adjustment for their correction, or 
else leave them uncorrected. Those who confound the two 
adjustments by such methods as the above are therefore taking 
a short cut to perform both of them at once — and slighting both. 
The better way would be to adjust for positions as perfectly as 
possible, then turn back to sections (669, 675, 679,) and adjust 
the isochronism properly to correct for the remaining position 
errors. 

Before leaving this subject, I would say that the custom 



THE WATCH ADJUSTER' S MANUAL. 311 

among experts, and even those who consider themselves first- 
class, is first to get a large vibration in the two horizontal 
positions, equalizing the two rates by rounding the ends of the 
balance pivots; secondly, make the rate in the hanging positions 
equal to that in the horizontal by altering the poise of the bal- 
ance (718); thirdly, make the rates in the two transverse 
quarters like the others by setting the hair spring excentrically 
(722) as required. In this way they get the watch adjusted " for 
all positions." This may do for practical jobbing, when the 
pay is small, but I think the reader will agree with me that put- 
ting balances out of poise and hair springs out of center does 
not deserve to be called first-class work unless the mechanical 
faults have previously been removed as completely as they can 
be. In that case, such alterations are excusable, because 
nothing else can be done. With strictly first-class watches for 
example, that method of adjusting would give the best practi- 
cable results. 

(731.) Testing stock watches. — The foregoing directions are 
for adjusting watches and chronometers. For merely testing 
stock watches, a much simpler procedure will suffice. The 
watch should have a good free motion when half wound up, 
and, to the eye, the motion should be the same in all positions. 
To test it by timing, set it exactly with the regulator, and run 
it for 6 hours in each position, with the mainspring wound the 
same in each trial. The first trial is with pendant up, and the 
time in that position is the rate of the watch, and the standard 
of comparison for the other positions. Then test with pendant 
down, dial up, and dial down. In any of these positions it 
should not differ more than 3 seconds from the rate, (pendant 
up,) or it must be considered not closely adjusted. If it is a 
really fine movement, it can also be tested in the other two ver- 
tical positions, and should not vary from the rate more than 5 
seconds per day in any one of the positions tested. Ordinary 
watches are adjusted for only two positions, pendant up and 
dial up. Better ones are also adjusted for the two transverse 
quarters, that is, if pendant up is XII up, the transverse positions 
or "quarters" would be III up and IX up; if the hanging 
position is III up, the quarters would be XII up and VI up. 

(732.) Example of position-ti??iing adjustment. — A watch which 
gains 12 seconds in 24 hours, hanging, i.e., pendant (XII) up, 
is tried in the horizontal positions, and gains 4 seconds in 12 
hours, dial up, and 2 seconds in 12 hours, dial down. It is then 
tried for 12 hours, fully wound, in the other three vertical 
positions, or "quarters." With VI up, it gains 6 seconds; with 



312 THE WATCH ADJUSTER'S MANUAL. 

Ill up, it gains 8 seconds; with IX up, it gains 2 seconds. As 
the watch gained the same amount in the hanging position and 
the two horizontal positions, (4" -\- 2" = 6",) it is said to be 
isochronous. 

(733.) But dial up gains on dial down, and the end of the 
balance pivot is flattened a trifle in the former position to nearly 
equalize them. The rate with XII up and VI up is the same 
(for the same length of time, 12 hours,) but there is a position 
error in the other two quarters, and we draw out the timing 
screws nearest to III, to make the gain less with III up and 
greater with IX up, and the gain is then 5 seconds in each 
position. This is both easier and better than bending the spring. 
The mean-time screws are then drawn out, reducing the rate to 
-\- 3 seconds in 24 hours, and the position errors vary from — i 
second to + 2 seconds daily, in the different positions. All of 
the trials are made at 60° Fahrenheit, with the watch fully 
wound at the beginning of each trial. It will be noticed that 
the timing adjustment is short and easy, which is owing to the 
fact that the watch had previously been through a rigorous 
mecha7iical adjustment^ as already recommended, and was in first- 
rate mechanical condition, with the arcs equalized, and there- 
fore required only a few finishing touches. 

(734.) Explanatio7is of positions record. — By reference to the 
explanations of the isochronism record, (689,) this one will be 
readily understood. The " hours" refers to the length of the 
trial. No separation is made between the hours and the error 
of rate, as the + or — mark between them is suflicient. A 
space is left at the head of the column before the word "up," 
for the insertion of the dial figure which is up, at the place 
where the dots are. The amount of winding and the extent of 
the vibration are important items, and should be noted. If all 
the position trials are made with the same amount of winding 
and the same arc, they can all be entered on the same line, as 
shown. But if different, only the trial or position in which that 
winding or arc was used should be entered on the line with it. 
If the arc or motive force was varied by the controller, state 
the fact in the last column — also, any other point of importance. 



THE WATCH ADJUSTER'S MANUAL. 



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PART EIGHTH. 

THE ADJUSTMENT FOR HEAT AND 

COLD. 



CHAPTER XXXIX. 

Compensation. 

(736.) Adpistment to tejtiperatures. — The compensation for heat 
and cold completes the list of adjustments which are found in 
the modern fine portable timepiece. It may be accurately ad- 
justed to positions and isochronism, and yet be utterly untrust- 
worthy for time. Every change in the weather, or other 
circumstance, however trivial or unavoidable, which warms or 
cools the movement, will produce an error in the rate, which 
may vary from a few seconds to as many minutes in a single day. 

(737.) Methods of compefisating. — The first attempts to remedy 
these errors were by contrivances acting upon the hair spring — 
an example of which is the " parachute regulator," often seen in 
old escapement or anker watches, which opens or closes the pins 
of the regulator by means of a compensating quadrant, as the 
temperature changes. It would be very interesting to examine 
the various methods of compensating for the effects of heat and 
cold which have been proposed at different times, and trace the 
progress of invention from the first crude ideas through succes- 
sive discoveries and improvements, but the practical character 
of this book forbids. At the present day the means almost uni- 
versally employed for that purpose are embodied in what is 
generally known as the expansion or chronometer balance, more 
correctly termed the compensation balance of ordinary con- 
struction. 

(738.) The compensatio?i halaiice of ordinat-y construction consists 
of a center-bar, upon the ends of which the rim is supported. 
The rim is made of two different metals or alloys, one of which 
expands and contracts more than the other when exposed to 
changes of temperature. The two metals which are generally 
employed are steel and brass. (Balances of other materials are 



THE WATCH ADJUSTER'S MANUAL. 315 

described in Chapter IX.) The brass expands and contracts 
much more than the steel, and it is by means of this difference 
that the rim "compensates." When the balance is exposed to 
heat it expands and the watch would consequently run slower. 
But this is counteracted by the action of the rim, which, from 
the brass being outside and expanding more than the steel, 
curves the free end of the rim inward, and carries the weight or 
screws upon it towards the center of the balance. In cold the 
whole balance contracts, and, from being smaller, would vibrate 
more rapidly, but the brass exterior contracting more than the 
steel, tends to straighten the rim and carry its screws outward, 
thus neutralizing the effects of the cold. As has been explained 
in Chapter X, the virtual size of the balance is governed by 
the distance of the center of its weight from the axis, and the 
object of the compensation is to keep that distance at the proper 
point in all temperatures. 

(739.) What is competisatedfor. — Change of temperature affects 
the time kept by a watch or chronometer in different ways: — 
ist. Heat expands the balance, making it, for the time being, 
of larger diameter, and causing it to vibrate more slowly. 2d. 
It expands the hair-spring, making it stronger but at the same 
time diminishes its elastic force to a still greater degree, and 
thus causes a loss of time. 3d. It acts upon the mainspring in 
a similar way, greatly weakening the motive force. 4th. It 
affects the fluidity of the oil, affecting the balance vibrations 
and the quickness of action of the escapment. 5th. It affects 
the action of pivots in their holes, and all similar parts, when 
they are closely fitted. The opposite of the effects above noted 
takes place in cold. We will consider each of the actions 
separately. 

(740.) Action of heat oti the balance. — It is popularly supposed 
that the object of compensation is to neutralize the effect pro- 
duced by the expansion of the balance. But that effect is only 
about one-sixth of the total effect produced by the heat upon 
the watch. A plain balance, when exposed to a rise of 60° 
Fahr. , will cause a loss, by its expansion, of about 60 seconds 
in 24 hours, while the total loss by the action of heat upon the 
watch will be from 385 to 393 seconds per day, so that from 
325 to T,2)2t seconds per day must be attributed to other causes 
than the expansion of the balance. If the latter was all we had to 
compensate for, the compensation would be comparatively easy. 

(741.) Action of heat on the hair sp?'ing. — The expansion of a 
spring by heat of course increases all of its dimensions, i.e.., its 
length, breadth and thickness, by an equal percentage. The 



3i6 THE WATCH ADJUSTER'S MANUAL. 

increase in length makes the spring weaker, but the increase in 

width and thickness makes it stronger. If we represent its 

length by /, its breadth by b^ and its thickness by /, the formula 

for calculating the strength of a spring i^S) from its dimensions is 

bf 
S— — . If we could suppose that the heat doubled its length, 

and the other dimensions in the same proportion, the increase in 
width would double its strength, but the increase in length would 
reduce it one-half, so that the effects of the two would be just 
equal, and leave the strength as it was at first. The increase 
in thickness would make it2X2X2=:8 times as strong as at 
first, and the watch should go so much faster. The fact that it 
actually loses, however, shows that there is some very potent 
weakening influence at work, to cause a loss of over six minutes 
per day, instead of the gain we should naturally expect. 

(742.) Action of heat on the elastic force of the spring. — That in- 
fluence is generally supposed to be the loss of elastic force 
caused by heat; and to it is attributed the loss of six minutes 
per day, in place of a gain. Such a belief is clearly a mistaken 
one. No doubt, heat does lessen the elastic force, and cause a 
large portion of that loss, but it does not cause the whole of it, 
for the other effects of heat mentioned in section (739) are in- 
cluded in the total loss. But this effect upon the spring is much 
greater than that upon the balance, and the compensation is 
therefore needed for the correction of the errors of the spring, 
much more than for those of the balance. It is found that the 
variation in the force of the spring almost exactly follows the 
changes of temperature, i.e.., the elastic force of the spring varies 
inversely with the temperature, becoming greater as the tem- 
perature becomes lower, and less as the temperature rises. 

(743.) Better 7naterial than steel needed. — As most of the errors 
in different temperatures are caused by the action of steel in 
heat, the remedy should be sought in some other material, whose 
elastic force is not affected so much by heat. Glass springs 
have been found to be much less affected. Dent experimented 
with springs of different materials, his chronometers having bal- 
ances made of glass, and which were therefore not compensated. 
One of them, with a steel spring, lost 6 minutes and 25 seconds 
in a day for a rise of 68° Fahr. , while another with a glass 
spring lost only 40 seconds. As steel only expands about 25 
per cent more than glass, the different effect must be due to the 
fact that the elastic force of the glass spring is less affected by 
heat than that of steel. Glass is not suitable for hair springs^ 
but some other metal or alloy may perhaps be found which 



THE WATCH ADJUSTER'S MANUAL. 317 

would be nearly as insensitive to heat as glass, or, at least, much 
less so than steel. The compensation could then be easily- 
made almost perfect. Palladium springs are less affected than 
steel, but they do not compare with glass in that respect. Gold 
springs are affected more than steel. 

(744.) Action of heat on the mai7ispring. — As heat causes a loss 
of elastic force in steel springs, (and perhaps in those of all 
other materials,) it must necessarily weaken the mainspring, 
also. This effect I have not seen mentioned before, but as the 
loss is so enormous in the hair spring, it must be correspondingly 
important in the mainspring, causing a serious diminution in the 
motive force, smaller arcs of vibration, with the attendant errors 
of rate unless the hair spring is isochronal, and also less ability 
to overcome imperfections in the train, dirt, etc. Whatever the 
loss may be, it forms a part of the error which the compensation 
is expected to provide for. 

(745.) Action of heat upon the oil. — The action of heat can 
hardly be said to be detrimental, unless it is sufficient to damage 
the oil, or make it so fluid that it runs from the pivots, etc., or 
permanently change its consistency by evaporating or drying it 
up. But the effect of lowering the temperature is well known. 
By thickening the oil, it causes a clogging or retarding action 
upon the vibrations; makes the escapement more sluggish, 
slower in starting and throughout the action; the oil is more 
sticky and adhesive, catches the dirt more easily, and retards all 
rubbing surfaces; and whenever the fitting is very close, in 
either side-shake or end-shake, very seriously affects the motion 
of the moving parts. When the balance pivots are closely fitted, 
the effect of low temperature upon the running must be consid- 
erable, and that has to be covered by the compensation. 

(746.) Action of heat upon closely fitted pivots^ etc. — As steel ex- 
pands much more than the jewels employed for holes, a closely 
fitted pivot could easily expand so much as to become almost 
bound in the jewel hole. Other closely fitted parts can become 
too close in the same way, especially if oiled with a rather thick 
lubricator. On the other hand, if the pivot or bearing runs in 
a brass hole, cold could contract the brass around it sufficiently 
to cause binding. The same thing can occur when the end- 
shake of an arbor or staff is very close. The holes being held 
by cocks or other parts of brass, which contracts in cold more 
than the steel, they are drawn together upon the shoulders or 
pivots, or too close for freedom. There is no doubt that the 
running is seriously affected by this fault in many watches, and 
that, also, must be covered by the compensation. 



3i8 THE WATCH ADJUSTER' S MANUAL. 

(747.) What is coi?ipensationl — Having our balance in the 
watch and running, let us consider what it should do. We have 
already seen that in heat the greater expansion of the brass 
exterior of the rim will curl the segments inwards, and carry the 
screws or weights towards the center. In cold the greater con- 
traction of the brass carries the weight outwards, and thus com- 
pensates for the contraction of the entire balance, which would 
otherwise cause a gain in time. Obviously, the weight should 
be carried inward in heat, and outward in cold, just enough to 
make up for the expansion or contraction of the balance, the 
effects of heat or cold on the hair-spring, and all other changes 
resulting from the change of temperature. When this is accom- 
plished, the compensation is correct, and the watch is said to be 
compensated or adjusted for heat and cold. Whether it does so 
or not can only be told by actually trying it in heat and cold. 
Even when marked "adjusted," balances seldom can be safely 
guaranteed to be closely compensated, till they have been tested 
and their actual performance ascertained. The custom with 
most manufacturers is to test them, and those which perform 
with tolerable accuracy are marked "adjusted," while the rest 
are sold as unadjusted. Watchmakers who have many cus- 
tomers for fine watches can frequently make it profitable to buy 
these unadjusted movements, and adjust them themselves, 
thereby raising them to the value of the adjusted movements of 
the same class. The process is somewhat tedious and trouble- 
some, but this is largely compensated for by the number 
which may be under way at the same time, with but little more 
trouble and expense than one would be, and the experience 
gained is of great value to any watchmaker who aspires to do 
fine work. 

(748.) Over-compensatio?i. — Instead of the weights or screws 
on the rim being moved inward and outward just enough to 
compensate for heat and cold, they may be moved too far, or 
not far enough. In the former case, the watch is said to be 
"over-compensated." It will gain in heat, because the weights 
are carried too near the center, thus making the balance virtu- 
ally smaller; in cold, the weights will be carried too far out- 
wards, and cause a loss of time. The segments act too strongly, 
but as we cannot change their action, we must find some means 
to lessen its effects. It would not do to lessen the weights, as 
that would cause a gain in time by making the balance lighter. 
But we can move the weight or screws back from the cut ends 
of the segments towards the center-bar. The motion of the 
segments inward and outward being greatest at their free ends, 



THE WATCH ADJUSTER' S MANUAL. 319 

the further back we place the screws, the less they will be 
moved. So that we can regulate the effect produced to almost 
any degree. For it is evident that if the weights were placed 
just at the ends of the center-bar, there would be no compensa- 
tion at all, except that produced by the weight of the segments 
themselves. And we have the entire length of the segments as 
a range for the weights, according to the effect we desire. 
Sometimes the action of the segments is so strong that they 
compensate too much, even when the screws are all moved back 
as far as they can be. In such case, we must substitute lighter 
screws in place of those nearest to the ends of the segments, 
and correspondingly increase the weight of those next to the 
center-bar. 

(749.) Under-co7?ipensation. — On the other hand, if the watch 
loses in heat and gains in cold, the weights are not carried far 
enough to produce the required effect, and it is said to be 
"under-compensated." The remedy for this is the opposite of 
that for over-compensation, viz: to move the weights or screws 
nearer to the ends of the segments, and increase the effect pro- 
duced by their motion. In making these changes, the screws 
must, of course, be moved in pairs, to prevent destroying the 
poise of the balance. Take out one of the screws, and change 
to another hole, nearer the end, if we wish to strengthen the 
compensation, or further from the end, if we desire to weaken 
it. Then move the screw which is exactly opposite to it, in 
the same way. We frequently need to move several pairs, and 
not merely one hole, but perhaps change their position by sev- 
eral holes, according to the indications of the trials. If the 
compensating action is so weak that even massing the screws at 
the ends of the segments does not produce sufficient effect, we 
can substitute heavier screws for those nearest the ends, and 
lighter ones for those further back, — as, for instance, screws 
of gold or platinum for those of brass or aluminum; and the 
reverse may be done for over-compensation. But in making 
these changes, the total weight of the balance must be kept the 
same, otherwise the rate will be altered. 

(750.) When a balance is properly compensated, the adjust- 
ment is not altered by changing the hair spring, or changing its 
length in bringing it to time, although it may be considerably 
longer or shorter than before, or than the old one was. The 
explanation of this lies in the fact that the heat or cold affects 
the spring in the same proportion, or percentage, whatever its 
length may be. For instance, if we suppose that the heat is 
sufficient to expand a spring one-fiftieth in length, it does not 



320 THE IV A TCH ADJUSTER'S MANUAL. 

matter what the real length may be. One spring may be twice 
as long as another; then the increase of length in the former 
will be twice the amount of that in the latter, — but both will be 
increased by one-fiftieth. So if the cold increases the effective 
strength of a spring ten per cent., the precise strength of the 
spring is immaterial. We are now only concerned with the 
proportion or ratio by which its strength is changed, and having 
compensated our balance to cover that progressive increase or 
decrease of strength found at the temperatures for which it is 
adjusted, the compensation will be correct for any other hair 
spring having that progression, i.e.., having about the same 
form, nature and temper. But if a soft spring be substituted 
for one hardened and tempered, or the reverse, or its temper 
considerably changed, then the progression will be altered, and 
the compensation would require a readjustment to suit the 
changed conditions. For it must be remembered that the rate 
depends upon the absolute quantity of effective force in the 
spring, but the compensation is affected only by the ratio of its 
increase or decrease under the influence of different tempera- 
tures. Such a spring can easily be fire-hardened and tempered, 
as described in section (263), and so avoid such trouble. 



CHAPTER XL. 

Apparatus for Adjusting the Compensation. 

(751.) In adjusting the compensation for heat and cold, we 
need an apparatus for obtaining an elevated temperature which 
may be of any degree required and may be maintained nearly 
constant for a considerable time; and another for producing 
cold in the same way. The former is called the adjusting-oven, 
the latter the cold-box. Many different constructions are in 
use, and some of them are described herein. When only an 
occasional watch is to be tested or adjusted, any simple and 
inexpensive means available may be adopted for producing heat 
or cold ; care only being taken that the heat never exceeds 120°, 
which is as high as can be employed without danger of injuring 
the oil, or perhaps the movement. The movement must also be 
so inclosed as to be protected from dust or moisture, as, by a 
closely fitted movement box, with the glasses set in wax. And 
when great accuracy is required and the tests are short, it should 
be remembered that the duration of the trials must be com- 
puted as beginning after the movement has become thoroughly 
heated or cooled to the proper temperature in every part, which 



THE WATCH ADJUSTER' S MANUAL. 



321 



may take from half an hour to an hour. By this means, the 
times of exposure to the proper degrees of heat and cold will be 
alike. But if it is set and then put into the oven or cold-box, 
unless they were so constructed as to occupy the same length of 
time in attaining the required temperature in each case, the 
times during which it would actually be affected by the proper 
degree of heat or cold would be different, and cause an apparent 
error even when the compensation was correct. 

(752.) For testing in heat, some watchmakers put the movement 
in a tight tin box, which they bury in a vessel of sand which has 
been heated on a stove, in the oven, or in any other convenient 
way, and its temperature is kept as uniform as possible by fre- 
quent examination of a thermometer also immersed in the sand. 
Others use a cubical box of tin, zinc, or copper, which is divided 
into four or five air-tight compartments by means of horizontal 
metal partitions inside. The upper compartment should be 
large enough to take in a thermometer with the watches to be 
tested, and then tightly closed. It is well to have a double 
glass window in the door in the top, so that the thermometer 
can be watched without opening the chamber. Heat slowly 
by means of a small alcohol lamp underneath, till the thermom- 
eter shows the proper temperature, where it should be kept, 
either by reducing the size of the 

flame or moving it further from [| |~| 

the bottom of the box, or else by I , , j , ^ , , J 

alternately removing and replac- 
ing the lamp as needed. It is 
well to have a wood or paste- 
board casing to set over the box, 
leaving the bottom exposed, to 
prevent loss of heat by radiation, 
and preserve a more uniform 
temperature. 

(753-) Adjusting-oven. — A very 
complete apparatus, and one not 
expensive, can be made as shown 
in Fig. 52. This consists of a 
reservoir containing water, made 
of zinc or copper, the bottom 
portion about eight inches front, r 
by six back, and two deep, with 
two side branches four or five 
inches high and about one inch deep. The bottom and branches 
extend from front to back inside the casing. These branches are 
21 




Fig. 52. 



322 THE WATCH ADJUSTER' S MANUAL. 

closed over at the top, and have each a short pipe extending to 
the outside of the casing, for use both in putting in water, and 
allowing the safe escape of the vapor arising from the heated 
liquid. These tubes should ordinarily be stopped with a loose 
plug of paper or cotton, to prevent evaporation. Every joint of 
this reservoir must be securely soldered up, so that no moisture 
or vapor can enter the chamber containing the movements. 
The water should not fill it quite to the bottom of the pipes. 
One or two glass shelves, for receiving the watches, are sup- 
ported by wires or cleats soldered on the sides of the branches, 
and at such a height as to bring them about midway up the sides 
of the branches, and leave unobscured the scale of the ther- 
mometer fastened at the back of the chamber, or on the inside 
of the door. It will be observed that the front, back and top 
of this chamber are formed by the wood casing, leaving the 
reservoir containing heated water only below and at the sides of 
the movements. Experience has shown that the temperature 
is more even when arranged in this way than when the source 
of heat surrotmds the watches. 

(754.) The casing should be either of thick wood, or made 
double, with an air chamber between the walls, which is prefer- 
able but not indispensable. Pine, whitewood, or any soft wood 
will answer. Not only should the door fit the front of the case 
tightly, (or be packed with tailors' listing,) but the bottom of 
the reservoir should fit snugly both to the box and the door, to 
prevent the fumes from the lamp beneath entering the chamber. 
Two doors can be used, one reaching up to the bottom of the 
watch chamber, the other opening into the chamber and reach- 
ing to the top of the box. In the upper door and the top of the 
casing, double glass windows are inserted to allow of observing 
the movements and the thermometer without opening the door. 
One glass should be fastened to the outside of the wall, the 
other to the inside, making a tight, non-conducting air-chamber 
between them. 

(755.) Automatic heat regulator. — A compound bar of steel and 
brass, fastened by one end to the back of the chamber, regulates 
the heat by the motion of its free end, which curves and straight- 
ens similarly to the compensating segments of the balance. 
The brass is double the thickness of the steel, which may be a 
piece of clock spring, while the former is any hard or springy 
brass, the two being soft-soldered together in the form of a 
common magnet, with the brass outside. To one end is riveted 
or soldered a flat piece for screwing it in position. When fin- 
ished, this bar should be well washed and cleaned from the 



THE WATCH ADJUSTER'S MANUAL. 323 

soldering fluid, (212.) To the free end is attached a cord which 
passes over a grooved pulley and through a small hole to the 
outside of the casing, thence to the valve which regulates the 
supply of gas to the burner. When oil or alcohol is used, the 
cord passes down inside the casing, through a tube which passes 
through the bottom portion of the reservoir, to the wheel which 
turns the wick of the burner. This tube is soldered in both the 
upper and lower sheet of the reservoir perfectly water-tight, and 
should extend down a little lower than the row of holes provided 
for the exit of the heated air from the lamp chamber, so that 
the fumes will not rise through it into the movement chamber. 
For this reason the tube should be of small diameter. 

(756.) The gas valve, or wick turner of the lamp, is turned 
by means of a lever attached to it, having a weight near the 
end heavy enough to pull it down. This lever is supported by 
the cord, w^hich is tied to it, and it is only when the motion of 
the compound bar allows the cord to yield that the lever can 
drop and shut off the gas, or reduce the flame of the lamp, more 
or less, according to the motion of the bar. When the temper- 
ature falls, the bar contracts, draws up the cord and lever, turns 
on the gas, or enlarges the flame, and an increased temperature 
in the reservoir results. The cord is attached to the lever at 
such a distance from its pivot or center of motion that the 
movement of the bar will give sufficient motion to the lever. 
For instance, if the free end of the bar moves half an inch for 
the increase of temperature from the mean to 95°, or any other 
degree chosen for the heat-extreme, then the cord should be 
attached to the lever at a point where that half-inch of motion 
will turn the valve or wick down enough to just maintain the 
desired temperature, and no more. This can be told by a little 
trial, moving the lamp to suit the changes of the cord. If pre- 
ferred, the temperature can first be raised to the right degree in 
the chamber, then turn down the wick or valve to about the 
proper amount, as above mentioned, attach the lever to the 
valve in a horizontal position and connect the cord. Then any 
increase or decrease of temperature from that degree will cause 
the lever to be moved in the proper direction to correct it. 
The gas valve, or wick turner, should be made to operate very 
easily, and the lever made with a sort of spring clamp to slip on 
the thumb-piece of the valve, or the wheel of the burner, and 
hold itself tightly in place. In the case of a gas cock, the lever 
might be permanently fitted to it, if desired; but with a lamp it 
could not, because there is no certainty in the position of the 
thumb-wheel. Every trimming or alteration of the wick will 



324 



THE WATCH ADJUSTER' S MANUAL. 



change the position of the wheel, and the lever must be capable 
of being slipped on after the right position is found. 

(757.) Air holes are made in the lamp chamber, through the 
casing, in two rows. The upper row should be an inch or so 
below the bottom of the reservoir, in order to retain the most 
highly heated portion of the air in the chamber, in contact with 
the reservoir, — only allowing it to escape after it has yielded 
up some portion of its heat and fallen to the level of the holes. 
Another row of holes for entrance of air is made near the bot- 
tom of the casing. Three or four half-inch holes are generally 
enough for each row, and all should be made on the same side, 
or on adjacent sides, to prevent wind blowing through the 
chamber, and disturbing the flame or putting it out. The 
height of this lamp chamber should be made to conform to the 
requirements of the lamp or flame which it is proposed to use 
for heating. A still cheaper oven is made by omitting the side 

door, and having only the 
opening at the top. Any sim- 
ilar construction can be adopt- 
ed. But the use of iron or tin 
is objectionable, because very 
liable to become magnetized. 

(758.) Logan s adjusti?tg oven 
is a well known construction, 
which can be bought already 
made. It is shown in the cut, 
Fig. 53, which will be readily 
understood after reading the 
foregoing explanation of the 
requirements of such appara- 
tus. The dimensions are: 
height, 9f inches; width, 5 
inches. Base, 5|- inches; 
height, 3-| inches. It is heated 
by a gas burner, — the gas pipe, 
^, coming from the left side, 
and entering the box at the 
bottom, 4. The flow is auto- 
matically regulated by steel 
and brass compensating lami- 
nae in the horizontal tube 2, seen in the center, which they 
control by approaching towards or receding from openings in 
the vertical pipe j, which contains a perforated plug, adjusted 
by the milled head at the top. A small side opening in the 




THE WA TCH ADJUSTER'S MANUAL. 



325 



plug allows sufficient gas to pass to avoid extinguishing the 
flame, even when the main gas supply is closed. 

(759.) The cold-box. — For testing watches in cold, they may 
simply be kept in a cold room, if the season is suitable, or 
placed in a tight 
metal box and kept 
in an ordinary refrig- 
erator. It is much 
better, however, to 
have an apparatus 
constructed with spe- 
cial reference to that 
use, an example of 
which is shown in 
Fig. 54. It consists 
of a tight wooden 
box, preferably with 
double walls, packed 
between with saw- 
dust, and lined with 
zinc so as to be water- 
tight. The zinc has 
the same shape as the 
box, and will set down into it when the cover is off. The cham- 
ber is soldered water-tight to the zinc casing, in the position 
shown, open only in front. The door is attached to the wooden 
box. The ice is contained in the water-tight zinc casing, which 
is supported by the wooden casing around it. It comes to an 
edge at the bottom, both for convenience of drawing off the 
water by a cock inserted at the lowest point, and to insure con- 
tact of the ice with the metal chamber which holds the move- 
ments during the trials. This chamber may be about six inches 
square, and there should be at least i^ inches space between it 
and the sides of the casing, to prevent the ice packing and clog- 
ging, instead of passing on to the bottom. This whole space — 
above, at the sides of, and below, the metal chamber, is to be 
filled with broken ice, well packed down with a flat-ending stick. 
One or two glass shelves are used in the chamber, as in the 
oven. The thermometer is here attached to the door, and win- 
dows for observation are omitted, as the condensation of mois- 
ture upon them by the cold air within would prevent seeing 
inside. Besides, the box must not be opened till the trial is 
ended, (762,) and the thermometer is only used as an assurance 
that the temperature was correct up to the moment of opening 




326 THE WATCH ADJUSTER' S MANUAL. 

the box. Legs are attached to support the box ; and when the 
cover is removed, the whole top should be open for convenience 
of filling and packing the ice. 

(760.) Degrees of cold. — If ice alone is used, a pretty constant 
temperature of about 35° will be maintained. When a greater 
cold is desired, common coarse packing salt should be mixed 
with the powdered ice, throwing in two or three handfuls of 
ice, then a handful or two of salt, mixing and packing down 
with a stick; then another layer, and so on. This will give a 
temperature of about zero. As the ice melts by contact with 
the salt, and the water passes off, it should be poked down 
occasionally with a stick and a fresh supply added at the top. 
When the cold-extreme chosen is only 50° or 55°, less ice must 
be used, and no salt. Sometimes it will be sufficient to keep a 
supply of ice on the top of the chamber, not being necessary to 
pack the whole space around it. For so moderate a degree of 
cold as that, the ordinary household refrigerator will answer 
every purpose, by enclosing the watches in an air-tight box. 
For regulating the temperature of the chamber in the cold-box, 
a compensating bar would be useless, but is sometimes used to 
indicate the temperature within the chamber. In that case it is 
attached to the door, and the cord passes over a pulley, with 
its axis penetrating the door, and on the outside carrying a 
pointer, which is set to point to an index corresponding to the 
degrees of the thermometer inside. But it is much better, as 
well as less troublesome, to choose for the cold-extreme a tem- 
perature which can be easily produced, and kept at the same 
point without watching and regulating it, — as, that of 35°. 

(761.) For breaking up the ice, the best way is to make a 
stout wooden box, about a foot square and six inches deep 
inside. Put in ice enough at a time to fill it about an inch deep 
when broken up. Pound it with a hard-wood pestle, with per- 
fectly flat bottom, say three or four inches square. A stick of 
stove-wood, with one end cut down small enough for a handle, 
makes a good pounder, — its weight helping along the powdering 
process. Break the ice pretty fine, leaving no pieces over an 
inch square, and empty each boxful into a tub, till enough has 
been broken up to fill the cold-box, before you begin to pack it. 
When packed, protect it from the sun, and throw an old rug or 
piece of carpet over it to keep it as cool as possible and save 
ice. 

(762,) Precautions in using the cold-box. — When the watch is 
removed from the cold box and opened, the moisture in the 
air condenses on the cold metal, and is sure to rust all steel 



THE WATCH ADJUSTER'S MANUAL. 327 

parts. Many plans are employed to prevent this, as it is well 
known that the slightest rust on the balance spring will destroy 
and prevent its perfect action. Some chronometer makers go 
so far as to take the balance and hair spring out and wash them 
in alcohol or benzine to absorb any film of moisture and prevent 
rust. But probably as good a way as any is, to notice the 
difference between the watch and the regulator, as quickly as 
possible, and then place it in the oven with chloride of calcium 
(763), and let it slowly warm up to the temperature of the room, 
(which may take 10 or 15 minutes,) when it can be safely 
opened and handled. Always remember not to open a refrig- 
erated watch in a warm room till it has been brought to or 
nearly to the temperature of the surrounding air. If possible, 
open it only in a cold room. 

(763.) Also remember to always place in the chamber, just 
before closing it, a watch crystal containing a teaspoonful of 
chloride of calcium in powder or fine lumps. This substance is 
a powerful absorbent of moisture, and prevents the moisture of 
the air in the chamber being deposited on the watch as it be- 
comes cold. It must be kept in a tightly closed bottle until the 
moment of using, to prevent it from absorbing moisture and 
becoming useless. The portions used can be kept in another 
bottle until a quantity is collected, then heat it on a metal plate 
over an alcohol lamp to dry it out, when it can be used again. 
It can be obtained from any chemist's shop. Place the crystal 
where the currents of air pass over it in the chamber. 



CHAPTER XLI. 

Adjusting the Compensation. 

(764.) The adjustment of the compensation consists in changing 
the positions and weights of the screws, until the balance com- 
pensates correctly for the effects of heat and cold and the watch 
will keep the same rate in all temperatures. As already ex- 
plained in sections (748) and (749), if it gains in heat and loses 
in cold, (when running correctly at the mean temperature,) the 
screws or weights must be moved back from the ends of the seg- 
ments towards the center bar. If it loses in heat and gains in 
cold, they must be moved towards the ends of the segments; if 
the error is not corrected when the screws are all massed at 
the ends of the segments, metallic washers are put under the 
screw heads, or heavier screws are used. Whenever the weight 
of the adjusting screws is thus increased or diminished, the 



328 THE WATCH ADJUSTER'S MANUAL. 

weight of the timing screws must be correspondingly changed to 
keep the total weight of the balance exactly as it was at the 
beginning, else the rate will be disturbed. In all cases, move 
two opposite screws at the same time, and equally. If, however, 
it should become necessary to alter the hair spring, in length or 
otherwise, the timing must be again gone over, as carefully as 
at first. 

(765.) Requisites of the adjustvietit. — It is always desirable, and 
is supposed to be the case, that before the trials for compensa- 
tion commence, the movement shall be in perfect order, — the 
escapement particularly being as closely adapted as possible, 
adjusted to positions, the hairspring closely isochronized, regu- 
lated closely to mean time, and observations made by a regula- 
tor whose rate may implicitly be depended upon as correct and 
uniform. If there is any doubt on any of these points, the 
adjustment trials should be repeated, before changing the 
screws, to ascertain if the results coincide. If not, it is evident 
that the errors arise from some other source than the compensa- 
tion, — perhaps the balance is defective. If the adjustment to 
positions has not been made, the movement must be placed in 
exactly the same position during each trial. 

(766.) Range of the adjustment. — The range of temperature for 
which the balance is adjusted varies with the ideas of the man- 
ufacturers, or the climate in which the chronometer is expected 
to be used. For temperate climates, a range from 50° to 90° is 
thought to be sufficient. Many makers adjust only for 50° to 
70°. For hot climates, 60° to 90° is considered ample to in- 
clude all ordinary vicissitudes of temperature. 50° to 85° will 
generally cover the temperatures to which ship chronometers are 
exposed on board. And instruments have been carried with 
expeditions to the polar regions without experiencing any 
greater range than that, owing to the care taken of them. But 
pocket watches should be adjusted for a range from 35° to 95°, 
in order to cover the temperatures to which they will be fre- 
quently exposed. During the day they are kept warm by con- 
tact with the person, while at night they are often exposed to 
the temperature of freezing, zero, or even lower. Some Ameri- 
can watch companies have adjusted from about zero to about 
130°. This, however, is rather more than is necessary or 
beneficial, as the residuary error spoken of in a subsequent 
section becomes very considerable in so extended a range. And 
besides, the errors at such extreme temperatures do not always 
indicate or correspond to those found at the more ordinary tem- 
peratures in which it is commonly used. For a balance may 



THE WATCH ADJUSTER'S MANUAL. 329 

perform quite satisfactorily in the latter, and then afterwards 
show a considerable error when exposed to the former, so that 
such tests are not necessarily trustworthy guides as to the real 
value of a balance. We should adjust for a range that will in- 
clude the reasonable exposures to be expected, and then divide 
up the error between the mean and the two extremes, so that it 
shall nowhere be very large. 

(767.) Length of trials. — The length of time the trial should 
last also varies according to the circumstances of the case. In 
the first trials, six hours will generally be sufficient to show the 
error clearly. But as each correction diminishes the error, the 
length of the trial must be increased to twelve, and finally to 
twenty-four hours. When great accuracy is required, chronom- 
eters are often kept for a week in heat and cold alternately. 
In all cases, the same period must be taken for heat, cold and 
mean temperature, so that the results can be safely compared. 
If the trial in one temperature is for six hours, the others must 
also be for six hours. The longer trials not only give time for 
the errors of compensation to accumulate to an appreciable 
quantity, but they have the further advantage of averaging 
errors due to other causes, as lack of isochronism, mechanical 
defects, etc. In the final trials, in order that the adjustment 
may be relied upon as perfect, the chronometer is kept a week 
in cold, then a week in heat, and lastly a week in cold again. 
This gives time to develop the actual performance of the instru- 
ment. Now test the poise of the balance, both at the mean 
temperature and in extremes, as in sections (154, 779), and the 
variations between the times in the hanging and horizontal (dial 
up) positions. Then finally test for a week at the mean tem- 
perature, and get the rate as correct as possible if it has been 
disturbed by any of the changes made during the adjustment, or 
by the tests, for when a chronometer has been going for some 
time at a very high or low temperature, the rims frequently 
" set" a little, causing a change of rate at mean temperature. 

(768.) Proper order of trials. — Everything being ready, as in 
section (765), the watch being closely regulated to mean time, 
and set exactly, or its variation from the regulator noted down, 
we subject it first to cold for six hours, (767,) and put down the 
precise error of time in the adjustment-book (780) ; then ex- 
pose to heat, and again note down the error. Many workmen 
expose first to heat, then to cold, but I prefer the order recom- 
mended, for the reason that when the movement is taken from 
the cold-box it condenses upon itself the moisture always pres- 
ent in the atmosphere, owing to its being colder, causing a 



330 THE WATCH ADJUSTER' S' MANUAL. 

liability to rust. But by then exposing the movement to heat, 
it is dried off and all danger obviated. A good custom followed 
by many workmen, is to expose first to heat, then to cold, then 
to heat again, to verify the correctness of the first heat trial. 
This is for the final tests. 

(769.) Distu7'bing the rate. — After altering the screws to change 
the compensation, the trials should include not only cold and 
heat, but also mean temperature, to see if the alterations have 
disturbed the rate. If so, the two (or four) mean-time screws 
should be changed to correct that, at the same time that the 
other screws are moved to change the compensation. If the 
error of rate is very small, as a second or so per day, it will 
generally be sufficient to turn one of the timing screws as little 
as it can be seen to move. But the screw thus changed should 
be noted, so that any similar change afterwards required may 
be made upon its opposite, otherwise the balance might be 
thrown out of poise. It must also be remembered that the tim- 
ing or " quarter-screws" should not be moved from their holes 
for the purpose of correcting the compensation, but the screws 
on either side of them may be moved /(^j^/ them, to the other 
side, if necessary. The timing screws are not designed for act- 
ing upon the compensation, but only for correcting the rate or 
the poise. 

(770.) Rating and conipejisating at the same time. — After both 
the timing and compensating screws have been changed as 
above, the next series of trials should commence with a test at 
the mean, to ascertain the rate, then in cold and heat, compar- 
ing the three results to find the error of compensation. For 
instance, if the rate was discovered to be two seconds slow in 
six hours; the loss in cold, four seconds; the gain in heat, six 
seconds, then, if the rate had been correct, the real loss in cold 
would have been only two seconds, and the real gain in heat, 
eight seconds. (This is on the supposition that the watch is set 
exactly, at the beginning of each trial.) This was the actual 
effect of the compensation, but the error of rate increased the 
apparent loss and decreased the apparent gain. It is in the 
highest degree important, however, that the rate be as nearly 
correct as it can be got before testing the compensation, for it 
is often hard enough to make out the real cause of the error 
even then, and any further complication would make " confusion 
worse confounded," with the beginner. Some workmen follow 
a different system. Having first determined the rate at mean 
temperature, they test in cold, alter the screws for the error, 
test again in cold, and so on till the error in cold is removed; 



THE WATCH ADJUSTER' S MANUAL. 331 

then test in heat, and proceed in the same way; then test in 
cold again, removing the error in each extreme before they leave 
it. This is quicker than the method above mentioned, but is 
not so good, unless a saving of time is the paramount object. 

(771.) Irregular co??ipensation. — As already stated, if the watch 
loses in cold and gains in heat, the compensation is too strong, 
termed over-compensated, and the remedy is to move the weights 
back on the segments. If it gains in cold and loses in heat, it 
is under-compensated, and the screws should be moved towards 
the free ends of the segments. But we find in practice that 
there is a greater difference between the rates in cold and mean 
than there is between heat and mean, so that the rate cannot be 
adjusted so that it will be the same at the mean and both ex- 
tremes. If the watch gains in both heat and cold, the compen- 
sation is too strong in heat and too weak in cold. If the screws 
were moved back to lessen the error in heat, we should thereby 
increase the error in cold to a nearly equal extent; or, if we 
lessen the error in cold by moving the screws forward, we shall 
increase the error for heat. For this there is no remedy. All 
we can do is to get the error equal in both heat and cold, which 
will of course reduce the error in each extreme to the smallest 
amount possible. In exceptional cases, where a chronometer or 
watch will seldom be exposed to one of the extremes, we can 
locate nearly all the error in that extreme, and thus free the 
other extreme, in which it will be generally used, almost entirely 
from variation. For instance, if the balance is adjusted for 35° 
and 95°, as the two extremes, the middle temperature will be 
65°. Now if the instrument will only be exposed to tempera- 
tures between 65° and 95°, we can correct the error for heat by 
moving the screws in the proper manner to make the mean tem- 
perature rate and heat rate alike, and so place all the error in 
the extreme of cold, where it will rarely or never trouble us. 
Nearly as good results may be obtained with such balances by 
adjusting them from 65° to 95°, with the mean at 80°, but it is 
more trouble to adjust for a limited range, both from the diffi- 
culty of keeping the temperature just at the exact point, — which 
is more necessary in this case because the entire range of tem- 
perature is so small that any variation would reduce it to little 
or nothing, — and from the greater difficulty of noting the error 
of rate produced by so slight a change of temperature, requiring 
a longer time for it to accumulate into an observable amount. 

(772.) If the watch loses in both heat and cold, (as compared 
with the mean temperature rate,) which is usually the case, the 
compensation is too weak in heat and too strong in cold, i.e., 



332 THE WATCH ADJUSTER' S MANUAL. 

the weights or screws are not carried fast enough, or far enough, 
towards the center of the balance, in heat, to compensate for 
the effects of heat on the balance and the hair spring; and they 
are carried outwards in cold too rapidly, or too far, causing a 
loss of time in both cases. For this error, like the one just 
mentioned, there is no remedy. We can only hide it, or get it 
out of the way, as above noted, (771.) All the foregoing errors 
are due to the construction of the balance being such that it 
cannot secure the weights being moved in accordance with the 
law which governs the number of vibrations, and in such a way 
as to compensate not only for the effects of heat and cold upon 
the balance itself, but also upon the hair spring, the oil, and the 
mechanism generally. 

(773.) Middle temperature ei-ror. — Even when the balance is 
as nearly correct in construction and performance as it is possi- 
ble to make it, it is very seldom practicable to adjust it so that 
there is no error at all when the temperature is changed. The 
smallest error is found when the difficulty in the balance is over 
or under-compensation. In these cases, by moving the screws 
judiciously on the segments, the variation between the rate at 
the two extremes and that at the mean can be reduced to a very 
slight error. This residuary error, which remains in spite of all 
we can do, is technically termed the middle temperature error. 
Even the best made and most carefully adjusted chronometer 
balances, when adjusted to give the same rate at 35° and 95°, or 
the two temperatures chosen for the heat and cold extremes, 
will have a different rate at the mean. Of course, the more 
limited the range of temperature between the extremes, the less 
this error will be; but it is never entirely eliminated in balances 
of the ordinary construction, varying from a part of a second to 
several seconds per day, according to the range, the skill and 
patience of the adjuster, and the peculiarities of the balance, its 
hair spring, etc. Sometimes the rate at the extremes will be a 
trifle faster than the mean temperature rate, but, almost invari- 
ably, when the rate has been made alike at the two extremes, it 
v/iil be slower than the mean temperature rate; that is to say, 
the chronometer being regulated at the mean temperature, it 
will lose time as the temperature becomes higher or lower. Or, 
if the rate be made the same at the mean and either extreme, 
the loss will be all located in the other extreme, as already 
stated. 

(774.) Locating the error. — Chronometer makers generally get 
the rate as correct as possible at the two extremes to which the 
instrument will probably be exposed, and it will then (almost 



THE WATCH ADJUSTER' S MANUAL. 333 

invariably) gain as the temperature changes from either ex- 
treme towards the mean, and will of course gain most at the 
mean temperature — generally from 2 to 4 seconds per day. For 
temperatures outside of the extremes it will lose. Watches, 
however, are more often adjusted for mean temperature, and 
when the rate is correct at the mean, there will be a loss of 2 to 
4 seconds at either extreme, and still more outside of the ex- 
tremes. In many cases, they are adjusted to get the rate cor- 
rect at the mean and one of the extremes, and the total error 
will then be located at the other extreme, i.e.^ a loss of from 4 
to 8 seconds per day. 

(775,) Seco7idary or auxiliary compensation. — As the ordinary 
compensation balance is not capable of being manipulated so as 
to remove this residuary error, various devices have been added 
to it for producing a separate and additional adjustment to ac- 
complish that purpose — some acting in cold, some in heat, and 
some at all temperatures. This additional compensation is called 
secondary or auxiliary compensation, and balances provided 
with them are termed balances with auxiliaries. These, how- 
ever, are generally added only for some special requirements, 
(766, 789,) and have not come into any general use in pocket 
watches and instruments sold for purely commercial purposes, 
being mostly unstable, and therefore unreliable for a permanent 
action, besides their cost being greatly increased. As the num- 
ber of these devices is probably several hundred, acting on all 
sorts of principles, and by all sorts of means, it is impossible to 
give directions for constructing or adjusting even the more 
prominent makes. (I describe the two kinds most used, below.) 
Frequently the conditions of success are known only to the 
makers, or could only be ascertained by many experiments and 
failures. It will generally be found more profitable and satis- 
factory not to meddle with auxiliary compensations or unusual 
constructions at all, unless the workman has skill and experi- 
ence enough to make them himself. In that case, he would 
probably be able to study out the principles of the particular 
device before him, without any further instruction than his 
knowledge of the theory of compensation. His experience will 
then have taught him both wisdom and caution in making altera- 
tions. The average workman would do well to confine his 
practical operations to the primary compensation, or adjustment 
of the ordinary compensation balance, and, before going any 
further than that, he should again read and remember the advice 
in the last paragraph of the introduction. 

(776.) Molyneux's auxiliary for heat. — This acts in the heat 



334 



THE WATCH ADJUSTER'S MANUAL. 



extreme. It consists of a short segment or arc, either of steel, 
or of steel and brass laminae similar to a section of a balance 
rim, arranged inside of the real rim near its cut end, and carried 
by a light spring /, Fig. 55, screwed to the end of the center bar 
by a foot piece 6. Ordinarily, this stands free, with the heel 2 
resting against the rim at a, and is carried around by the 
balance the same as the rim. But if it is desired to increase 
the compensation at the heat extreme, a banking screw, 5, in 
the end of the balance segment hits the arc 2, j, at the proper 
time, and forces it to move inward with itself. The w^eight of 
the auxiliary is thus added to that of the rim and the effect in- 
creased. The banking or adjusting screw, 5, in the end of the 
long segment of the rim can be adjusted to touch the auxiliary 
sooner or later, as required, and one or more screws, 4^ in the 
latter vary its weight. The spring 7, which sustains the auxil- 
iary arc, yields easily when the balance rim (by screw 5) presses 
against the auxiliary. 7 is the usual mean-time screw or nut. 





Fig. 55. 



Fig. 56. 



This device can be made of compensating laminae, with the 
steel inside, like the balance, in place of i^ 2, j, in which case 
it compensates by itself, besides aiding the balance to compen- 
sate. In Mercer's chronometer balance this construction is 
employed. The auxiliary arc is screwed to the rim at the end 
of the center-bar, and carries screws at its free end, which can 
be moved to vary the effect, as is done with the balance. It is 
sometimes used to lessen the error in cold, and then the steel 
lamina is outside of the brass, and the banking or adjusting 
screw is in the short segment of the balance rim. The fore- 
going description will sufficiently explain how to adjust them. 

(777.) Poole's auxiliary f 01' cold^ Fig. 56, is merely a slip of 
brass J, (5, rigidly screwed to the outside of the balance rim at 
the center bar by a screw 4^ and extends a short distance along 
the long segment. A banking screw 5 in the end of the slip 
strikes against the segment when it moves too far outward and 
stops further outward movement there, but leaves the free end 



THE WATCH ADJUSTER' S MANUAL. 335 

of the segment still at liberty to respond to cold. This banking 
screw is turned in or out to vary the time (or temperature) at 
which the rim banks against it, as required for removing the 
error in cold. It can be placed further to the left when a greater 
effect is desired, i is the usual mean-time screw with its nut, 2. 

(778.) Finishing the adjust7nent. — Whenever any changes are 
made which affect or may affect the rate, /.<?., the time at mean 
temperature, a careful test of the rate should first be made as a 
standard of comparison for subsequent tests. Also, whenever 
any change might affect the isochronism of the hair spring, that 
should be tested, by varying the arcs of vibration, in the same 
position, and at mean temperature. And testing at mean tem- 
perature does not mean testing at any temperature which hap- 
pens to prevail in the testing room at the time, but at a certain 
fixed temperature, which has been chosen as the mean between 
the two extremes for which the watch is being adjusted. The 
testing room must be kept at that temperature. 

(779.) After the compensation has been perfected, the poise 
is then tested, both at mean and extreme temperatures (154, 
291), and tests are also made for any position errors at mean 
temperature. If it is a fine watch or chronometer, the position 
tests are repeated at extreme temperatures, i.e., test in the hang- 
ing and the horizontal positions in cold and in heat. If any errors 
are found and corrected, the compensation is again tested, to 
see if the corrections have affected it. If no corrections were 
made, the horizontal positions tests in heat and cold would 
suffice to show if the compensation is correct. Lastly get the 
rate at mean temperature as perfect as is possible to do, and the 
watch or chronometer can honestly be called "fully adjusted." 
When only the compensation is to be adjusted, (not for positions 
or isochronism,) the hair spring should be fitted as directed in 
Chapter XVIII, the balance poised, get the compensation cor- 
rect, test the poise, if any change is made in it then test the 
compensation, and finally rate the watch. 

(780.) Rating book, or rating sheets, for compensatitig. — For use 
in adjusting the compensation, the workman will find that paper 
ruled as shown on the following page, (338,) will be very con- 
venient, and will greatly simplify the work and assist in avoid- 
ing mistakes. Many workmen set the watch exactly with the 
clock at the beginning of each trial, but that involves consider- 
able trouble, and is not at all necessary. It is only requisite to 
note the exact difference between the watch and clock at the 
beginning and end of each trial. A comparison of the two will 
show the exact gain or loss during the trial, while any other 



336 THE WATCH ADJUSTER'S MANUAL. 

system will cause confusion and frequent mistakes. The form 
shown, (782,) gives all the data needed, is easy to fill out, and 
will be found preferable to the usual forms for practical use. 

(781. ) Example of record of adjustment. — A careful study of the 
record given on the following form (782) will afford the workman 
a better idea of the method of adjusting and of making a record 
of it, than any amount of explanation alone could do. At the 
head is sufficient description to identify the watch. The first 
column gives the date of the trial, and the second column states 
its duration. The third and fourth columns contain the data of 
all trials in cold, the fifth and sixth those of trials at mean 
temperature, and the seventh and eighth columns those in heat. 
The temperatures chosen for the adjustment in this case are 
60° for the mean, and 35° and 85° for the extremes. The last 
column is for miscellaneous memoranda, which may explain the 
circumstances connected with the trial and need to be remem- 
bered or recorded. In such matters it is never safe to trust to the 
memory, and all such points should be at once recorded in detail. 

(782.) Form for ratitig sheet. — [See page 338.] 

(783.) Recording the difference from the regulator. — It will be 
noticed that in the record of the first trial, there are two differ- 
ences from the regulator. The first one, in parentheses, is the 
difference from the clock at the beginning of the trial, while the 
principal difference, below the former, is found by comparing 
the watch at the end of the trial. The first difference is given 
as + i' 12", which shows that the watch was not set, but its 
error merely noted at the beginning of the trial. The safest way 
is to always state the difference at the beginning. If the watch 
was set with the clock state that fact, as is done in several trials 
on the sheet. If the watch is compared with the clock at the 
end of one trial, and without alteration is immediately subjected 
to another trial, it is not absolutel)'' necessary to state the differ- 
ence at the beginning of the new trial, because it would be 
merely repeating the record already made of the difference at 
the end of the previous trial. In the trials on April 4, the differ- 
ence at the beginning is thus omitted in each case, and it is 
understood that the difference at the beginning of the trial is 
the same as that stated at the end of the last preceding trial. 
But, as before stated, it is much safer to state it in plain figures 
each time, as is done in all the other trials. 

(784.) Recording the error. — It will also be noticed that there 
are two entries of the error, in each case, in the trials for heat 
and cold. The reason of this is, that we have to make allow- 
ance for the error of rate. In the record, the watch had a 



THE WATCH ADJUSTER'S MANUAL, 337 

mean-time error of 10 seconds per day, and even if the com- 
pensation had been so perfect that there was no compensation 
error at all, in either heat or cold, the watch would still show an 
error of 10 seconds per day. Consequently, that error would not 
be an error of the compensation, and in order to ascertain what 
the real compensation error is, we first record in parentheses 
the variation which has occurred during the trial, and below we 
enter ///<? r^^/ ^rr^/- after allowing for the daily rate. Thus, in 
the first trial of April 4, the difference from the regulator at the 
beginning was -{- i' 22", and at the end was -1- i' 52", showing 
that the watch gained 30" during the trial — which we enter in 
parentheses. But 5" of that gain was due to the error of rate, 
(12 hours, at 10" per day,) which leaves + 25" as the real error 
of the compensation in cold. In the second trial of April 4, the 
watch fell back from + 1' 52" to + i' 24" during the trial, the 
actual loss of time was therefore —28", which we enter in the 
parentheses. But the real error in heat was 5" more, (on ac- 
count of losing —28", in spite of the daily-rate gain of +5",) 

or — zz"' 

(785.) Cojnputi?ig the real error. — The easiest way to find the 
real error is to write down the difference from the clock at the 
beginning of the trial, + i' 52", add to this the error of rate, 
-\- 5", to find what the difference from the clock would be if 
there was no error in the compensation, — and compare this 
sum, -\- i' 57", with the actual difference from the clock at the 
end of the trial, -j- i' 24", and we find that the latter falls short 
to the amount of —Z?!'- I^ ^^^ trial of April 7, in heat for i 
day, the difference at the beginning was -|- 6", to this add -(- lo" 
for the rate-error for i day, making -j- 16" ; but the actual differ- 
ence from the clock at the end of the trial was only -|- 12", 
showing that the compensation error in heat caused it to fall 
back —4". While there was a gain of + 6" during the trial, 
as shown by comparison with the clock, there was a real loss of 
— 4" due to the compensation, for if there had been no com- 
pensation error, the difference would have been -|- 16". In 
making the allowance for rate, always compute the rate error 
for the length of the trial. 

(786.) The daily rate. — In the case recorded, the error at the 
mean temperature was called the daily rate. But, as before 
stated, the watch can be adjusted for either extreme, if pre- 
ferred, and then the error in that extreme would be the daily 
rate, and the error at mean temperature would be called the 
"real error" at that temperature. The computation of the 
daily rate is very simple, being the actual loss or gain of the 
22 



338 



THE WA TCH ADJUSTER'S MANUAL. 



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THE WATCH ADJUSTER' S MANUAL. 



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340 THE WATCH ADJUSTER' S MANUAL. 

watch during the trial, as compared with the clock. There is 
no allowance to be made for anything, except the length of the 
trial. In the two-days trial ending April i6, the watch gained 
-|- 4", and the daily rate was + 2", that is, it gains + 2" in 
each 24 hours. In the four-days trial it lost — 3", which would 
be — f" per day; in the seven-days trial it lost — 3-|-", which 
makes the daily rate - ^\ or — .5". The daily rate varied a 
little while being carried in the different trials, but that is to be 
expected in the pocket. But taking the last 13 days together, 
the mean daily rate for that period was only — |-", which might 
fairly entitle the watch to be marked " O. K. " 

(787.) Performance when adjusted. — If a watch keeps the same 
time in heat, cold, and mean temperature, it is accurately com- 
pensated. But this is very seldom the case with the ordinary 
compensation balance, except by accident, when the limits 
within which it is tried are very circumscribed. And it may be 
valuable to the novice to know what performance may be con- 
sidered good, average, or poor. Marine chronometers come 
nearest to perfection, and the very best made and most accu- 
rately adjusted instruments will gain daily, on an average, from 
five to six-tenths of a second more at the mean temperature than 
at the extremes, — supposing the former to be, say 70°, and the 
latter 55° and 85°. What may be called superior instruments, 
but not the best., will lose from one-tenth to one-fifth of a second 
for each degree of change of temperature either way from the 
mean, in twenty-four hours. When exposed to temperatures 
10° to 20° beyond these extremes, they will lose from one- 
quarter to three-quarters of a second daily, more than at the 
extremes. So regular are these variations, that when the con- 
nection between certain temperatures and the daily rate of a 
chronometer has been ascertained, the error of rate may be 
computed from observations of the thermometer. It will be 
sufficient for all practical purposes to determine the rate in the 
three temperatures for which it is adjusted, or the mean and the 
two extremes, and also say 15° outside of each extreme. In 
good instruments this connection will remain constant for a long 
time. The rate at the middle temperature is generally the 
standard or starting point, from which variations are noted. 
But cases sometimes occur when it is desirable to regulate to 
mean time at one of the extremes. As, if a chronometer is 
exposed habitually to a temperature of 95°, it can be regulated 
to mean time at that temperature, and the rate at the mean, or 
say 60°, will then be said to be so much slower or faster than 
the mean rate. Sometimes instruments are even adjusted with 



THE WATCH ADJUSTER' S MANUAL. 341 

three rates, — as if, for instance, the rate was made correct with 
mean time at 95°, but there was an error at the other extreme, 
or 35°, and still another rate at the mean, or 60°. The owner 
being furnished with a schedule of the rates corresponding to 
certain tem.peratures, could very easily compute the approximate 
error of his instrument by noticing the degrees on the thermom- 
eter, as already stated. 

(788.) Ordinary rates. — But the above-named results are 
shown only by the finest instruments. Ordinary chronometers 
will vary from one or two, up to five or six seconds daily when 
the temperature changes from the extremes for which they are 
adjusted, to the extent of 10° to 20° beyond. Pocket-watches 
may be made to come nearly as close as marine chronometers, 
but they seldom do so. AVatches marked "adjusted" will fre- 
quently vary from three to ten seconds in twenty-four hours, 
at the temperatures of 55° or 95°. A closely adjusted move- 
ment of the first quality ought not, however, to vary more than 
one to three seconds in twenty-four hours, w^hen the temperature 
is changed from the mean of 75°, to 55° or 95°. At the first 
trials, an unadjusted balance may vary from thirty seconds to 
two minutes in twenty-four hours heat or cold. And a variation 
of only fifteen or twenty seconds per day may be considered 
good for the first trials. All the foregoing rates apply only to 
the true compensation balance. Uncut balances, and the ordi- 
nary ones of one metal, will vary from three to six minutes when 
the temperature is changed from 35° to 95°. 

(789.) Marifie chronometers. — It must not be supposed that all 
ship-chronometers are good timepieces, and reliably compen- 
sated for heat and cold, for they are not. The majority of 
those in use are hired by the month, and in order to save a few 
shillings per month in the rent, shipmasters will deliberately 
choose instruments which are inferior in performance to a decent 
watch. So well is this understood by chronometer-makers, they 
are in a great measure deterred from experimenting for the sake 
of improving the compensation or from availing themselves of 
the discoveries of others, well knowing that they can scarcely 
hope to make good their outlay. A large share of their cus- 
tomers will pass by a really good instrument at a fair price, and 
take a " thing" offered by some competitor at a dollar less per 
month. It is only for some special uses that the most accurate 
performance is insisted upon, such as instruments for observa- 
tories, expeditions, watchmakers' time, and a few first-class 
vessels. As a matter of ordinary business, a perfect compensa- 
tion is not profitable, and consequently not sought for. Of 



342 THE WATCH ADJUSTER'S MANUAL. 

course, instruments designed for competition are made and ad- 
justed regardless of time, trouble, and expense, if only they 
may take the first or at least a leading place in the list of com- 
petitors. And for this purpose almost innumerable devices have 
been employed to reduce or remove the error which always re- 
mains after adjusting the ordinary compensation balance. The 
two auxiliaries which are most used by chronometer makers 
have been described in sections (776) and (777), with directions 
for adjusting them. 



INDEX. 



NOTE. — The references are to the numbers of the sections, not of the 
pages. 

A. 

Absolute isochronism, 547, 551, 554, 556, 660. 
Accelerating forces, 532, 533, 558. 

" short arcs, 593. {^ee Isochronal adjustment.) 

" " " by plus curves, 602 to 607. 

Acceleration in rate, 86, 381, 382, 3S3. 
"Adjusted" balances, distinguishing, 145, 347, 348. 
" " performance of, 787, 788, 789. 

Adjusting, automatic heat regulator for, 755, 758. 
" cold box for, 253, 759 to 763. 

" " " precautions in using, 762, 763. 

'• oven, 253, 751 to 758. 

Adjusting for isochronism, 657 to 6gi. 

" " " by terminal curves, 602 to 605. 

" " positions, 698 to 735. 

" " practical isochronism, 666. 

" *' theoretical " 664, 665. 

" " temperatures, 764 to 789. 

" " the different escapements, 389 to 514. 

Adjustment for heat and cold, 736 to 789. 

" " " " finishing, 778, 779. 
" " positions, 657, 692 to 735. 

" " " object of, 707. 

" realistic and practical methods of, 683. 

Adjustments, proper order of the, 658, 663, 698. 
Adjustment, the, for isochronism, 515 to 691. 

" " " difficult, 685. 

" " " object of, 708. 

" "of fuzee watches, 684. 

*' " " going-barrel watches, 684. 

" " " marine chronometers, 682. 

American watch springs, 96, 97, 103, 104. 
Angles, explanation of, 644. 
Annotating the book, 6. 
Arcs of vibration, see under Vidratt'on. 
" " " best for trials, 710. 

" " " large and small, 662. 

Auxiliary compensation, 775. 
" Molyneux's, 776. 

" Poole's, 777, 



344 INDEX. 



B. 



Balance, proper size and weight, for cylinder escapement, 318, 319, 
423, 456; for duplex, 449; rules for, 139. 
" spring, see under Hair Spring. 

*' timing-, 218 to 220. 

" top" of, 702. 
Balance, the, 27. 

*' compensation, 738, 

" effect of heat on, 740. 

" elastic, 524. 

" magnetized, 30, 31, 41, 695 (6). 

making heavier, 332, 333 ; lighter, 349. 
•• Mercer's, 776. 

" out of poise, 152, 154. See under Poising. 

" pivots bent, 29, 514. 

" " side pressure of, 544, 623, 660, 694. 

Balances, "adjusted," 347. 

" apparatus for hardening, 120. 

" calculating number of vibrations, 128 to 138. 

" " proper size of, 126. 

" correcting and finishing, 147 to 156. 

" excentric, 148 to 150, 695. 

" expansion or imitation, 348. 

" faults of expansion, 155, 695. 

" " plain, 156, 695. 
" irregular, 153. 

** making compensation, no to 117, 120, 122. 

" " expansion, 144. 

" " gold, 108. 

" " non-magnetic, 123. 

" " palladium, 123. 

" " plain, 108. 

" " spring-steel compensation, 118 to 121. 

" poising in extreme temperatures, 154. 

" proper size and weight for, 12, 125, 139, 694, 697- 

testing for, 141, 142. 
" selecting and testing, 124 to 146. 

" " " " compensation, 143 to / ^15, 

" tempering or setting, 151. 

Banking, in auxiliary compensation, 775, 776. 
" " chronometer escapement, 482, 505. 

" " cylinder " 406, 407. 

" lever " 472. 

Bar magnets, care of, 51. 

" " making and charging, 40. 

Bascule escapement, 473. 
Bath, cyanide, 63, 102, 
" lead, 62. 

" of melted alloy, 66, 67, 70. 
" oil or tallow, 66, 70, 78. 
" quenching, 65, 78. 
Beat, putting in, 2S7. 
" " " chronometer, 287, 487 to 490. 



INDEX, 

Beat, putting in, cylinder escapement, 288, 404, 405. 

" " " duplex, 287, 429, 

Beginning or end of terminal curve, 596. 
Bell, timing, 209. 
Bent pivots, 29, 514. 

" " to straighten, 415. 
Bending terminal curves, effect of, 631 to 636. 

" " " tweezers for, 250, 

Book, Prof. Phillips', 541, 549. 

" rating, see under Rating Sheets. 
Box chronometer, 170. 
Breguet elbow, 640 to 646. 

" " benders, 250, 643. 

" overcoil, 589, 606, 607. 

" " concentric arc on, 579 to 582. 

" " hardening in form, 96, 97, 102. 

" " regulator on, 579, 581, 651 to 654. 

" " shape of, 104, 638 to 656. 

" " terminal curve on, 647 to 649. 

" springs, 604; making, 95. 

fitting, 237, 242, 638. 

" " number of coils, 103, 104, 105, 637. 

" " pinning, 638. 

regulating by regulator, 354 to 358, 652 to 654. 

" " vise for holding, 253, 650. 

" " with concentric arc, 356 to 358, 652 to 654. 

Bulged hair springs, to correct, 262. 



Calcium, chloride of, in cold box, 762, 763. 
Calculating revolutions of fourth wheel, 185. 

" size and weight of balance, 124 to 127. 

" vibrations of balance, 129 to 138, 182 to 192, 264. 

Cannon pinion, 24. 
Cap jewels, 17 to 19. 
Care of magnets, 51. 

" " watches, 323 to 325, 334, 335. 
Center of gravity of Phillips' curves, 543 to 546. 

" square, 24. 
Central coil of spring, 274. 

Chloride of calcium, to absorb moisture, 762, 763. 
Chronographs, 176 to 179. 

" recording times by, 161, 180, 181. 

Chronometer, box or marine, 170. 

escapement, 473 to 514. 

" description of, 482 to 486. 

" drops in, 496 to 500, 572. 

" faults of, 474, 475, 476. 

" hair spring for, 474, 479. 

" in beat, 487 to 490. 

" oiling, 480. 

" proper condition of, 473 to 509. 

setting, 341 to 343. 

" to time, 510 to 512. 



345 



346 INDEX. 

Chronometer, timing in positions, 698 to 735. 
Clark's method of demagnetization, 42. 
Cleaning blackened steel, 59. 

" colored or tarnished steel, 60, 92, 103. 
Clock, secondary, 171. 

" standard, 157, 158. 
Coils of Breguet spring, number of, 103 to 105, 637. 
" cylindrical " " " 86, 397. 

" flat spiral " " " 103, 105, 397, 427, 453, 474, 479. 

" " " " distance apart, 547. 
•• '• " opening the, 260. 
Collet, pinning spring to, 273 to 277, 282. 
" poising the, 290. 
" -turning tool, 289. 
Color-piece, 81, 82. 
Coloring cylindrical spring, 81 to 84. 
" flat spiral " 94, 103. 
Colors for hardening steel, 64. 

" tempering " 66 to 68, 92. 
" " " palladium, loi. 

Common ideas on isochronism, 521, 528. 
Comparing vibrations by opposition, 221. 

" " " reversal or coincidence, 222. 

" " with another watch, 214 to 217. 

" " " timing balance, 218 to 223. 

" watch by the seconds hand, 367 to 375. 

" " " vibrations of balances, 366. 

" '* with an assistant, 375, 376. 

" " with the regulator, 365. 

Compensated for, what is, 739. 
Compensating, methods of, 737. 

" and rating at the same time, 770. 

Compensation, adjusting the, 764 to 789. 

" apparatus for, 253, 751 to 763. 

" auxiliary, 775. 

•• " Molyneux's, 776. 

" " Poole's, 777. 

" balance, ordinary, 291, 738. , 

'* changing spring does not affect it, 750. 

" for heat and cold, 736 to 747. 

" irregular, 771, 772. 

" natural, 389 to 514, 518. 

'* over-, 748; under-, 749. 

*• rating sheets for, 780 to 785. 

" requisites of, 765. 

" secondary, 775. 

Concentric arc on Breguet spring, 579 to 582. 
Contradictions, seeming, 14. 
Controller, motive force, 673, 674. 
Correcting the poise, 695. 
Counting, 193 to 209, 271, 272, 310, 311. 

" the vibrations of balance, 197, 208. 

'• *' " till reversal or coincidence, 205. 

Cracking, to prevent, 61. 
Criterion, for hair springs, 254. 



INDEX. 



347 



Cross-references, 7. 

Current, alternating, for demagnetization, 47. 
Curves, adjusting by the, 602 to 607. 
" effect of bending the, 631 to 636. 
" " the form of, 634 to 636. 

" "Excelsior's" theory of, 634 to 636. 
" forming the, 649. 
" minus, 596,598. 
" mixed, 596, 599. 
" of flat spiral spring, 629 to 636, 654. 

Phillips', 548, 549. 
** plus, 596. 
Cyanide bath for heating, 63, 102. 

" " " tempering, 72, 102. 

Cylinder escapement, 396 to 425. 

" " escape wheel in, 400, 414. 

" *• faults of, 408 to 415. 

" " hair spring in, 397. 

" " in beat, 404, 405. 

" " methods of isochronizing, 419 to 421. 

" " "natural compensation" of, 416 to 418. 

" " oiling, 424, 425. 

" " proper condition of, 396 to 407. 

" " setting, 345. 

" " testing the balance in, 421, 423. 

" " vibrations, 397. 

Cylindrical hair springs, 73 to 87. 

" " " coloring, 81 to 84. 

" " " hardening, 77. 

length of, 620. 
" " " making, 75. 

** " " number of coils, 86, 397. 

" " " pinning, 618, 621, 622. 

" " " poising, 299, 546. 

" " " polishing, 80. 

" " " ready made, 611. 

" " " tempsrmg, 80. 

" " " terminal curves for, 87, 612. 

" '* " " " changing, 624, 625. 

" " ** " " proper forms for, 617, 6ig. 



D. 

Daily rate, 362, 590, 600, 786; correcting, 678. See under Rate. 
Demagnetization, 38, 53. 

" apparatus for, 50. 

" Clark's method of, 42. 

" Maxim's " " 45. 

Mayer's " " 44. 
Waldo's " " 43. 

" of tools, etc., 52. 

" with alternating current, 47. 

" " electro-magnet, 48, 49. 

" " horse-shoe magnet, 46. 

Detecting position faults by extent of arcs, 704, 705. 



34S 



INDEX. 



Detecting position faults by timing, 709 ; in positions, 711. 
Dial, excentric, 334, 339. 
" fastening the, 21, 338. 
" imperfect, 334, 369, 373. 
" testing the, 340. 
Diameter gauges for springs, 210, 252. 
Difference between isochronal and positional adjustments, 707. 

" " the different escapements, 393. 

Different escapements, merits of the, 391, 392. 

" " require different treatment, 389. 

*' " the four, 389 to 395. 

" opinions on isochronism, 536 to 541. 
Distance of coils apart, 106, 547. 
Drawing hair-spring wire, 56. 
Drops, in chronometer, 496 to 500, 572. 
" duplex, 431 to 433, 571. 



E. 

Effect of bending the curve, 631 to 636. 
changing balance pivots, 569. 

" the coils of spring, 574. 

'* drops, 572. 
" " escapement frictions, 571. 

" " other frictions, 568. See under Frictions. 

" " length of spring, 560, 563. 

" " mode of attachment, 622, 624, 634 to 636. 

" '* motive force, 573, 697. 

" " poise of balance, 718 to 721. 

form of curve, 629, 634, 636. 
frictions greatest in short arcs, 556, 567, 568. 
heat on elastic force of spring, 742, 743. 
moving the regulator, 350 to 358, 584. 

" " " on Breguet overcoil, 57gto 581. 

pinning in even or fractional coils, 563 to 567. 
running down, 385. 

setting the spring excentric, 575 to 578, 633, 660, 694. 
the regulator pins, 585 to 588. 
Elastic balance, 524. 
Elastic force of the spring, 742, 743. 

Elasticity, imparting to steel, 55; to gold, 98, 99; to palladium, 100, loi. 
Elbow-forming tweezers, 260, 643. 
Electro-magnet, demagnetizing by, 48, 49. 
End-stones, 17 to 19. 
End or beginning of terminal curve, 596. 

" virtual, of spring, 591, 592. 
Enlarging a spring, 260. 
Error, personal, of observer, 180, 181. 
Errors, escapement, 696 (5), 714. 

frictional, separating, 675, 714. 
middle-arc, 662. 

" -temperature, 384, 773. 
must balance each other, 657, 669. 
of compensation, 784, 785. 
" isochronism, 558, 657, 668. 



INDEX. 



349 



Errors of poise, 695; trials for, 713. 
" " proportion or design, 697, 
" positional, 662, 694, 695, 
" rotating or varying, 695. 
Escapement frictions, 571, 694. 

" the chronometer, 473 to 514. 

" " " description of, 482 to 486. 

" *' " drops in, 496 to 500, 572. 

** " " faults of, 474, 475, 476. 

" " " hair spring in, 474, 479. 

" " " in beat, 487 to 490. 

" *• " oiling, 480. 

" " " proper condition of, 473 to 509. 

" " " setting to time, 341 to 343, 510 to 512. 

•* " " timing in positions, 698 to 735, 

" " " vibrations, 477, 478. 

'* the cylinder, 396 to 425. 

faults of, 408 to 415. 

" '* " " " cylinder, 401 to 403. 

" " *' " " escape wheel, 400. 

" " " " pinion, 414. 

•• " " hair spring in, 397. 

" •' *" in beat, 404, 405. 

" " " methods of isochronizing, 419 to 421. 

" " " "natural compensation" of, 416 to 418. 

" " •* proper condition of, 396 to 407. 

** " " testing size and weight of balance, 421, 423. 

" " " vibrations, 397. 

" the duplex, 426 to 450. 

" " " drops in, 431 to 433, 571. 

** " " faults of, 444, 445, 

" " " hair spring in, 427. 

" . " " in beat. 429. 

" " " "natural compensation" of, 446, 447. 

" " " proper condition, 426 to 443. 

" " " setting in, 344. 

" " " vibrations, 428. 

Escapement, the lever, 451 to 472. 

faults of, 472. 
" " " hair spring in, 453. 

" " " in beat, 455. 

" " " oiling, 457. 

" " " proper condition of, 451 to 471. 

" " setting, 345. 
Escapements, the, separately considered in Part Fifth. 

" " adjusting, 393, 395. 

" " four principal, 389 to 395. 

" " mechanical conditions required, 394. 

" " merits of, 391, 392. 

" " " Frodsham's opinion on, 391, 392. 

" " the "natural compensations" of, 393, 416 to 423. 

Even turns, 564 to 566 ; or fractional coils, 567. 
"Excelsior's" hair-spring tools, 224 to 244. 

" " " " mode of using, 229 to 237, 611, 659. 

" magnetism tester, 37. 



350 INDEX. 

"Excelsior's" method of detecting magnetism, 37. 

" " " making hair springs, 106, 107. 

" " " " spring-steel compensation balances, 

118 to 121. 
** motive-force controller, 673. 

" "Practical Treatise on the Balance Spring," see Intro- 

duction. 
" theory of flat spiral springs, 629 to 636, 

" " " terminal curves, 589 to 607, 629 to 636, 654. 

Excentric balance, 148 to 150. 

" dial, 334, 339; testing do, 340. 

spring, 575 to 578, 633, 660, 694. 
" " rules for setting, 722. 

Expansion balance, the, 144, 348. 
Experts, different opinions from, 608, 609. 

" information from, see Introduction. 
Extent of vibrations, measuring, 703. 

" " " varying, etc., 671 to 673. 

" " " detecting position faults by, 710. 

F. 

Faults of compensation balances, 155, 695. 
" " plain balances, 156, 695. 
" " hair springs, see under Hair Spj'z'ngs. 
" " poise, 713. 
" " proportion or design, 697. 
" " the chronometer escapement, 474, 475, 476. 
" " " cylinder " 408 to 415. 

" " " duplex " 444, 445. 

" " " lever « 472. 

" escapement, 696, 714. 
" positional, 665, 694, 704, 705, 711. 
" rotating or varying, 695, 
Finding proper number of vibrations, see under Balance and Vibra- 
tions. 
Finishing balances, 147 to 156. 
Fitting balances, 124 to 146, 147 to 156. 

" Breguet hair springs, see under Breguet. 
" cylindrical '' " " Hair Springs. 

flat spiral 
Flat spiral hair springs, adjusting for isochronism, 629 to 636. 

" central coil, 274. 

" cleaning, 92 ; coloring, 94. 

" distance of coils apart, 106, 547. 

" excentric, 575 to 578, 633, 660, 694. 

" " bending, 631. 

" fitting, 237, 242, 255 to 303, 627. 

" hardening, 92, 103, 263. 

" improvement suggested, 106, 107. 

" isochronizing, by excentric setting, 575 to 578, 694. 

" " " fractional coils, 567. 

" « » openness of coils, 574. 

" « « regulator, 584. 

« « « u pins, 5S5 to 588. 



INDEX. 351 

Flat spiral springs, making, common method, 88. 

" " modern American method, 102, 103. 

" number of coils, 103, 105, 397, 453, 474 to 479. 

" pinning to collet, 273 to 277, 282. 

" polishing, 93. 

" selecting, 258, 259, 268, 626. 

" " by hair-spring gauge, 265. 

« « " " " " rule for, 266. 

" " " vibrating balance, 269, 272. 

" taking up and letting out, 630. 

" tempering, 92, 103. 

" winding, 91, 103. 

" " tool for, 89, 90. 

Flattening hair springs, 261. 
Force, motive, varying the, 518, 573, 697. 

" " controller, 673. 

Form, changing the, 624, 625, See under Curves. 
" effect of, 634 to 636. 

" for Breguet overcoil, see under Breguet. 
" " flat spiral, 547, 575 to 578, 629 to 636, 660, 694. 

" " terminal curves, 87, 548, 589, 595, 612, 617, 619. 

•' reverts after bending, 625. 
Flexion, influences affecting, 533. 
irregular, 533. 
" isochronal, 536, 544. 

Fractional coils in hair springs, 567. 

" " •' " effect of changing, 567. 

Friction, effect of, 530 to 533, 556, 568, 569, 571, 601, 664. 
" " greatest in short arcs, 556, 557, 568. 

" " in different positions, 518, 693, 694. 

" errors, separating, 675, 714. 

" escapement, 571, 694, 696 (5), 714. 

Frodsham's opinion of the different escapements, 391, 392. 
Functions of terminal curves, 590, 594. 
Fuzee watch, adjusting for isochronism, 684. 

G. 

Gain or loss, 527, 557, 600, 601, 712. 
Gauges, hair-spring, 211, 212, 248. 

" " " using do, 265 ; rule for, 266. 

" " " for diameter of, 210, 252. 

" terminal curve, 616. 

Going-barrel watch, adjusting for isochronism, 684. 
Gold balances, making, 108, log. 

" hair springs, 98 ; properties of, 99. 
Gravity, center of, of Phillips' curves, 543 to 546. 
Grinding hair springs, 328, 329. 

H. 

Hair springs, altering, 327 ; in stud, 336. 

" " better material needed for, 743. 

" " bulged, 262 ; central coil of, 274. 

" " collet turner, 253, 289. 



352 INDEX, 

Hair springs, criterion for, 2S9. 

" " curves of, see under Curves and Termz?ial Ctirves. 

" " diameter gauges for, 210, 252. 

" " enlarging, 260, 

" " excentric, 575 to 578, 694. 

" " " rule for setting, 722, 

" " fitting, see under Breguet, Cyli7tdrzcal,SLn6. Flat Spiral. 

" " flattening, 261. 

" " gauges, 211, 212, 248. 

" " " using, 265 ; rule for, 266. 

" " grinding, 328, 329. 

" " hardening, 72. 

" " drawn, 263. 

" " heating, in lead, 62 ; in cyanide, 63. 

" " holding, 269, 270. 

" " " tools, 224 to 247. 

" " " vise, 253, 650. 

" " isochronizing, see under Isochronal, Isochronism, and 
Isochronous. 

" " number of coils, see under each escapement. 

" " pinning excentric, 575 to 578, 694. 

" " " in even coils, 279. 
« " level, 276, 694. 

" " " " and concentric, 277, 694. 

" " " to collet, 273 to 277, 282, 618, 621, 622. 

" " " " stud, 278, 281, 282, 284. 

*' " poising, 293 to 297, 546, 694. 

" " " difficulty of, 295, 296, 297. 

" •'• putting in beat, see under Beat. 

" " quick test for, 223. 

" " ruined, 257. 

" " selecting, usual way, 268. 

" " " by vibrating the balance, 269, 272. 

" " shaping tweezers and pliers, 249, 250. 

" " testing, 210 to 220. 

" " " by comparing with timing balance, 218 to 223. 

" " " " " " watch, 214 to 217. 

" " " " hair-spring gauges, 211, 212. 

" " " " opposition of vibrations, 221. 

" " " " vibrating the balance, 213. 

" " " " "weighing," 210. 

" " " freedom of, 285. 

" " timing by comparing balances, 305 to 309. 

" " " " counting vibrations, 310, 311. 

" " " " opposition of vibrations, 306. 

" " " " reversal or coincidence, 307. 

" " " for errors of poise, 713. 

" •* " " position errors, 711. 

" " " "in reverse," 721. 

" " " quick ways of. 305 to 311. 

" " " see under Tuning, Rating, and Regulating. 

" " vibrators, 247. 

" " weakening with acid, 330. 

" " weight of, 694. 
Hands, fitting the, 20 to 25. 



INDEX. 353 

Hands, fitting the, of the regulator, i66. 
" " seconds. 22, 337. 

" putting on and taking off, 511. 

" tool for, 512. 
" setting the, 319. 

" " " to seconds, 320, 341 to 345, 510 to 512. 

" should be in center of dial, 334, 338. 
Hardening and quenching bath. 65. 

" Breguet overcoil in form, 96, 97. 

" drawn and soft hair springs, 263. 

'• expansion balances, 120. 

" steel, 62; C5''lindrical springs, 77 to 79. 

" " colors for, 64. 

'* " temperatures for, 64, 78. 

Heat and cold, the adjustment for, 736 to 789. 
" effect on closely fitted pivots and parts, 746. 
" *' " the balance, 740. 

" " " " elastic force of the spring, 742, 743. 

" " " " hairspring, 741. 

" " " " mainspring, 744. 

" " " oil, 745. 
Heating, in cyanide, 63 ; in lead, 62. 

" the new way, 63, 103. 
Heavier, making the balance, 332, 333. 
Holder for Breguet springs, 253, 650, 
" " hair springs 224 to 246. 

" " holding watch in different positions, 699. 

Holding springs by putty powder, 627. 
Horseshoe magnet, for demagnetization, 46. 

I. 

Ideas, common, about isochronism, 521, 528. 

Imitation expansion balances, 348. ^ 

Imperfect dial, 334, 369, 373; testing do, , 340. 

Improper weight of balance, 125, 694, 697. 

Improvement in making hair springs, 106, 107. 

Impulse vibration of chronometer, 485. 

Influences, accelerating, 532, 533, 558. 

" affecting flexion, 533. 

" " friction in different positions, 693, 694. 

" " isochronism, 530 to 534. 

" disturbing, 534, 658. 

" retarding, 530, 531, 533, 558. 

Irregular balances, 153, 

" compensation, 771. 
" rate, 321, 322, 334. 
Isochronal adjustment, 515, 657, 660 to 685. 

" " true purpose of, 681. 

" " what it can do, 660. 

'* " " " cannot do, 661, C62. 

" errors must balance other errors, 657, 669, 675. 

" springs, action of, 280, 517, 522. 

" vibrations, 553. 

'* also see under Adjusting. 

23 



354 INDEX, 

Isochronism, 515 to 534. 

" common ideas of, 521, 528. 

" correcting the, 679. 

" depends on special adjustment, 609. 

" different methods of securing, 550; also, see under /s-c>- 

chronism, securing. 

" " opinions about, 536 to 541, 

" effect upon the, of moving the regulator, 350 to 358. 

" influences modifying it, 530 to 534. 

" law of, 551. 

" middle-arc error of, 662. 

" no one method always successful, 609. 

" only true test for, 525. 

" on what it depends, 535, 551. 

" practical, 547, 551, 554, 556, 660. 

" "quick test" for, 524. 

" requirements of, 520, 528. 

" testing the, 522, 523, 676. 

" theoretical, 536, 547, 554, 555, 660. 

" true explanation of, 556 to 558, 601. 

Isochronism said to depend — 

on balancing isochronal and other errors, 558. 

" the length of the spring, 537, 539. 

" mode of pinning, 538, 539. 

" relation of the ends, 539. 

" terminal curves, 541. 
Isochronism can be secured — 

by a certain length of spring, 560. 
•' " " allowance for adjustment, 560, 561. 

" " " rules for the length, 560. 

" altering the balance, 570. 

pivots, 569. 
" " " drops, 572, 

" " " escapement frictions, 571. 

" " " frictions, 568. 

" " " motive force, 573, 697. 

" even turns, see Pin?iing in even turns, below. 
" excentric spring, 575 to 578, 694. 
*' fractional coils, 567. 

'* " " effect of changing the coils, 567. 

" isochronous stud, 550, 559. 
" pinning in even turns, 564. 

" " " " principle of this method, 565, 566. 

*' regulator, on Breguet overcoil, 579 to 581. 
** " " flat spiral spring, 584. 

" *' " terminal curves, 582, 583. 

pins, 585 to 588. 
" taking up or letting out the spring, 563. 
" terminal curves, 589 to 610. 
Isochronized, soft springs cannot be, 533. 

" to ascertain if a spring is, 516. 

Isochronous springs, 535, 556, 558. 

" " practically, 660, 668, 671, 672. 

" stud, 550, 559. 

" theoretically, 660, 664, 668. 



INDEX. 355 



J- 



Jewel cupped on the back side, 726. 

" holes not in line, 695. 

" " not vertical, 694. 

" " side pressure in, 544, 623, 660, 694. 

Junction of terminal curve with the spring, 590, 594, 596, 

K. 

KuLLBERG, setting springs excentrically, 575 to 578, 660. 

L. 

Large and small vibrations, 662. 
Law of evidence, 688. 

" " isochronism, 551. 
Lead bath for heating, 62. 

Length, isochronism said to depend on, 537 to 539, 560. 
*' of trials for compensation, 767. 
" virtual, 591, 592, 593. 

lengthening, 599. 
Letting out and taking up the spring, 563. 
Lever escapement, 451 to 472. 

" setting the hands of, 345. 
Line, pivots not in, 674 (15), 695 (5). 
Linseed oil for tempering steel, 66, 70, 78. 
Location of the standard or regulator, 169. 
Long and short arcs, testing in, 386, 
Loss and gain, 527, 557, 600, 601, 712. 

" of rate in soft springs, 383. 

M. 

Magnetic metals, 35, 36. 

Magnetism, 30, 34; detector, 37; testing for, 37. 
Magnetized watches, 30, 31, 41, 695 (6). 
Magnets, 33, 694 (17). 

" bar, making, 40; care of, 51. 

** electro-magnet, 48, 49. 

" horse-shoe, 46. 

Making balance heavier, 332, 333, 348 ; lighter, 349. 

" hair springs, see under name of each form. 

" " " weaker with acid, 330. 

" steel elastic, 55. 
Mainspring, effect of heat on, 744. 

" see under Motive Force. 

Manner of attaching spring, 621, 622. 

" " " effect of changing, 622, 624, 634 to 636. 

Marine chronometers, adjusting for isochronism, 682. 

" " performance when adjusted, 787 to 789^, 

Maxim's method of demagnetization, 45. 
Mayer's " " " 44- 

Materials for making hair springs, 54, 98, 100. 
" better needed, 743 



356 INDEX. 

Manner of testing in positions, 706. 

" " " stock watches, 731. 
Marker, vibration-, 175. 
Mean daily rate, 363. 
Measuring extent of vibration, 703. 
Mercer's compensation balance, 776. 
Metallic baths for heating, 67, 68, 
Methods of adjusting for positions, choice of, 725. 

" " compensation, 737. 

*' " demagnetizing watches, 38 to 53. 

" " forming terminal curves, 612 to 615. 

" " isochronizing, see under head of Adjusting. 

" " " none successful in all cases, 609. 

" " " various, 550 to 610. 

*' " regulating, see under Ratitig, Regulating, and Timing. 

" " testing in positions, 706. 
Middle-arc error, 662. 

" temperature error, 384, 773. 
Minus curves, 596, 598 ; see also under Curves. 
Mirrors, getting time by, 172; positions for, 173, 174. 
Mixed curves, 596, 599. 

Modern American method of making hair springs, 102, 103. 
Molyneux's auxiliary or secondary compensation, 776. 
Motive force, adjusting isochronism by, 573, 697. 
" " controller, 673, 674. 

•• equal, 518; varying, 573. 
Movement holder, for different positions, 699. 
Moving regulator, effect on isochronism, 350 to 358, 579, 584. 

N. 

"Natural compensation," 393, 41610423, 446, 447, 518. 

New way of heating, 63, 103. 

Non-isochronous springs, action of, 517. 

Non-magnetic balances, 123. 

No one method of isochronizing applies in all cases, 609. 

Number of coils, for Breguet spring, 103, 104, 105, 637. 

" " " " cylindrical spring, 86, 474, 479. 

" " " " flat spiral, in cylinder, 397. 
" " " " " " duplex, 427. 
" " " " " " lever, 453. 

O. 

■'Observatory certificates for watches, 388. 

trials, 387, 388. 
'Observing the vibrations, 694 (20). 

Oil, effect of heat on, 745. 
" for tempering, 66, 70, 71, 78. 

Olive oil, 66. 

Only true test for isochronism, 525. 

Openness of coils, effect of, 574. 

Opinions on isochronism, conflicting, 536 to 541. 

Order of adjustments, 768. 
'^Over-banking, 408 to 410. 



INDEX. 357 

Over-compensation, 74S. 
Overrunning, in chronometer, 476, 498, 499. 
" " duplex, 444. 

P. 

Palladium balances, 123; springs, 100, loi, 611. 
Pendulum of regulator, 167, 
Personal error of observer, 180, 181. 
Phillips' book, 541, 549. 

curves, 542, 548, 549, 594, 597. 
" " center of gravity of, 543 to 546. 

" theory of terminal curves, 541 to 549. 

Pinning springs level, 276, 694. 

" " " and concentric, 277, 694. 

" " excentric, 575 to 578, 694. 

" " " rule for, 722. 

" " in even coils, 279, 564. 

'• " " principle of, 565, 566. 
•* " " fractional coils, 567. 

*' " " " effect of changes, 567. 

" Breguet springs, 103, 104, 105, 637, 638 ; see under Flat Spiral 

Springs. 
*' helical or cylindrical springs, 86, 397, 618, 621, 622. 

the flat spiral spring, 103, 105, 397, 427, 453, 474, 479. 
" to the collet, 273 to 277, 282. 

" stud, 278, 281, 282, 284. 
" " " testing freedom of, 285. 

Pivots bent, to straighten, 415. 
" not in line, 694 (15), 695 (5). 
" round, 694 (14), 695 (4)- 
" other faults, 694, 695. 
" side pressure of, 544, 623, 660, 694. 
Plus curves, 596. 
Poise, correcting the, 695. 
" errors of, 695. 

" trials for, 713. 
" rules for changing the, 718 to 721. 
" testing the, 302. 
Poising, 290 to 302, 

" difficulty of poising hair springs, 295, 296, 297. 
" the balance, 152; in extremes, 154. 
" " Breguet spring, 298. 

" collet, 290. 
" " compensation balance, 291. 

" *' cylindrical spring, 299, 546. 

" '* flat spiral spring, 294. 

*' the hair spring, 293 to 297, 546, 694. 
" tools, 251, 300; using, 300, 301. 
Polarity of magnetized pieces, testing, 40. 
Polishing cylindrical springs, 80 ; flat spiral springs, 93. 
Position errors, 662, 694, 695 ; balancing do, , 662 ; cause of, 705. 
" " detecting by extent of vibrations, 704, 705. 

" " " " timing, 709; by timing in positions, 711. 

" " " " " example of, 732, 733. 



35S INDEX. 

Position errors, trials for, 711. 
faults, 665. 
" holder for watches, 699. 
*' record or sheets, 734, 735 ; form for, 734, 
" of regulator, 282, 284, 315, 352. 
clock, 169. 

pins, 284, 315, 316, 352, 585 to 588. 
" " " " effect of moving, 350 to 358, 579, 584. 

*' " timing mirrors, 173, 174. 

Positional adjustment, choice of methods for, 725. 

" " difference from isochronal, 707. 

" " finishing, 729, 730. 

Positions, adjusting for, 698 to 735. 
" adjustment for, 681, 692. 

" " defined, 700 to 702. 

" " nature of, 699. 

" " requisites and apparatus for, 699. 

" friction in different, 518. 

" manner of testing in, 706. 

stock watches, 731. 
*• the four "quarters," 677. 

'* timing in, chronometers, 698 to 735. 

** " " cylinders, 422. 

•' duplex, 448. 
" levers, 698 to 735. 
Poole's auxiliary compensation, 777. 
Practical isochronism, 547, 551, 554, 556, 660. 
Practically isochronous spring, 660, 668, 671, 672. 
Practice needed, 5, 686. 
Precautions, with cold box, 762, 763. 
Prerequisites of regulating, 15, 314, 315. 
Pressure, side, of balance pivots, 544, 623, 660, 694. 
Prevent steel from cracking, 61. 
Progression of force, of spring, 352, 526, 532. 

isochronal, 544, 547, 552, 555. 
Proper condition, chronometers, 473 to 509. 
" " cylinders, 396 to 407. 

" " duplex, 426 to 450. 

" " levers, 451 to 471. 

" extent of vibrations for trials, 710. 
*' forms for terminal curves, 548, 589, 595, 609, 617, 619. 
" length " " " 619. 

" number of revolutions, 185, 

" " " vibrations, calculating, 182 to 192, 264. 

" " " " counting, 193 to 209, 271, 272. 

finding, 264. 
" " " " " by hair-spring gauge, 266. 

" '* " '* for chronometers, 477. 

" cylinders, 397. 
" duplex, 428. 
" levers, 454. 
" order for adjustments, 658, 663, 698. 
" " in regulating, 318. 

" time for regulating, 317. 
" weight and size of balance, for cylinder, 318, 319, 423, 456. 



INDEX. 359 

Proper weight and size of balance, for duplex, 447. 
Proportion or design, position faults of, 697. 
Putting in beat, 287. 

" " " chronometers, 287, 487 to 490. 

" " " cylinders, 288, 404, 405. 
" " duplex, 2S7, 429. 

" " " levers, 287, 455. 
Putty powder for holding springs, 269, 270. 

Q. 

"Quarters," the, 677. 

Quenching bath, 65. 

Quick test for isochronism, 524. 

" " " springs, 223. 

" ways of bringing springs to time, 305 to 31 1. 
Quickening the short vibrations, 593. 

R. 

Range of compensation, 766. 

Rapping, 411. 

Rate, acceleration of, 381, 382. 

" book, 377, see under Rate sheets. 

" causing it to correct middle-arc error, 384. 

" " " " " temperature error, 384. 

" change of, 381 to 383. 

" correcting the, 678. 

" daily, 362, 590, 600, 786. 

" errors in, 387. 

" loss of, 383. 

" mean daily, 363. 

" ordinary, of compensated watches, 788. 

" sheets, 377 to 380; law bearing on, 688. 

" " for compensation, 780 to 785. 

" " " isochronism, 687 to 691. 

" " positions, 734, 735. 

" " form for compensation, 782; for isochronism, 689; for 

positions, 734 ; for rate, 379. 

" testing in long and short arcs, 386. 
Rates, analyzing, 667 to 670. 

" observatory certificates for, 388. 

" required in observatory trials, 387. 
Rating, 361 to 388. 

" and compensating at the same time, 770. 

" duration of trials, 385. 
Ready made cylindrical springs, 61 r. 
Realistic and practical methods of isochronizing, 683. 
Recoil, 412. 
Recording times, apparatus for, 176 to 179. 

" " by chronographs, 161, 180, 181. 

Records, law of, 688 ; see under Rate Sheets. 
References, cross-, 7. 
Registering and comparing times, 176 to 181. 

" vibrations, 196 ; apparatus for, 194, 195. 



36o INDEX. 

Regulating, 304, 312, 350 to 353. 

" by altering spring, 327 ; in stud, 336. 

" " grinding spring, 328, 329. 

" " making balance heavier, 332, 333, 348 ; lighter, 349. 

" " regulator, 163, see under Regulator. 

** " timing or quarter screws, 346 to 348, 764. 

" " weakening spring with acid, 330. 

" choice of methods for, 326. 

'* how done, 334, 335. 

" in one temperature, 347. 

" prerequisites of, 315. 

" proper order in, 318. 

" " time for, 317. 

" to a fraction of second per day, 309. 

" varying watches, 321, 322, 334. 

Regulator, heat-, for adjusting ovens, 755, 758. 
Regulator, the, cap, 284. 

"" " effect of moving, on isochronism, 350 to 358,579, 584. 

" " isochronizing by, on Breguet spring, 579 to 581, 594. 

" " « u « flat spiral, 584. 

" " tt «4 ^jjg regulator pins, 585 to 588. 

" " " "on terminal curves, 582, 583. 

" regulating by, on Breguet spring, 354 to 358, 651 to 656. 

" " " with concentric arc, 356 to 358, 652 to 654. 

" on concentric arc, 582, 583. 

" pins, 16, 284, 315, 316, 352, 585 to 588. 

"" the, 283. 

" " position of, 282, 284, 315, 352. 

Regulator clock, 157 to 169. 

" " altering and setting, 163, 164. 

" " dial and hands, 165, 166. 

" " winding, 168. 

Relation of ends of springs, 539. 

Requirements and apparatus for positional adjustment, 699. 
" of isochronism, 520, 528. 

" " the different escapements, 389. 

Retarding influences, 530, 531, 533, 558. 
Reversal of vibrations, 307.^ 
Reverting of form after bending, 625. 
Revolutions, calculating number of, 185. 
Rigidity of curve of spring, 591. 
Rotating position faults, 695. 
Ruined springs, 257. 
Rule for changing the poise, 718 to 721. 

" " finding desired number of vibrations, 266. 
" " isochronizing by length of spring, 560. 
" " selecting springs by gauge, 266. 
" " setting the spring excentric, 722. 
Running down, effect of, 335. 

S. 

Secondary clock, 171. 

** compensation, 775 to 777. 

Seconds-hand, comparing watch by, 367 to 375. 



INDEX. 361 

Seconds-hand, fitting the, 21, 165, 337. 
" of regulator clock, 166. 

" setting to seconds, 320, 510 to 512. 

" should be central, 334 to 339. 

" taking off and putting on, 511. 

*• timing to fraction of second, 309. 

" tool for putting on, 512. 

Securing isochronism, different methods of, 550. 
Selecting and testing compensation balances, 143 to 145. 

plain " 124 to 146. 

Selecting hair springs, by gauge, 211, 212, 265, 266. 
" " " " vibrating balance, 269, 272. 

" " " usual way, 268. 

" steel, 57. 

Separating friction errors, 675, 714. 
"Setting," 413, 445, 472, 476, 499. 
Setting hair springs excentric, 575, 578, 660. 
" the regulator, 164. 
" . to seconds, 319, 320, 510 to 512. 
" " time, chronometers, 341 to 343, 500 to 512. 
" " " duplex, 344. 
" " " levers or cylinders, 345. 
Shape of Breguet overcoil, 104, 638. 
Shaping tweezers and pliers, 249. 
Short arcs, 662. 

" " to make faster or slower, 593. 
Shortening of spring, virtual, 598. 

Size of balance, 126 to 142, 318, 319, 423, 449, 456, 697. 
Soft springs cannot be isochronized, 533. 
Special adjustment, isochronism depends on, 609. 
Spring steel compensation balance, 118 to 121. 

" winding, 91, 103; tool, 89, 90. 
Springs, effect of heat upon, 741 to 743. 

" gold, 98, 99; palladium, 100, loi, 611. 

" holding, by putty powder, 627. 

" isochronous, 535, 556, 558. 

" " practically, 660, 668, 671, 672. 

" " theoretically, 660, 664, 668. 

" non-isochronous, action of, 517. 

" tools for fitting, 224 to 253. 

" " using, 229, 230, 234, 265 to 267, 611, 659. 

" vise for holding Breguet, 253, 650. 

Standard time, getting by observations, 162; by telegraph, 159. 

" " by box chronometer, 1 70. 

Steel, annealing, 58. 

" cleaning blackened, 59 ; tarnished or colored, 60, 92, 103. 
" coloring, 81 to 84, 94, 103. 
" drawing, etc., 56. 
" hardening, 62, 92, 96, 97, 103. 
" " colors for, 64 ; temperatures for, 64. 

" heating, the new way, 63, 102, 103 ; colors for, 64. 
" imparting elasticity to, 55. 

" tempering, 66, 80, 103; colors for, 69, 70, 71, 81 to 84. 
" " in air, 69 ; in cyanide, 72, 102 ; in melted alloys, 66, 

68, 71. 



362 INDEX. 

Steel, tempering in metallic baths, 67, 68 ; in oil, 66, 70, 71, 78. 

" " " tallow, 66 ; with thermometer, 72. 

" to prevent cracking, 61. 
Straightening balance pivots, 415. 
Stud, pinning to the, see under head of Pinning. 

" the isochronous, 550, 559. 

" removing the, 286. 

T. 

Taking off and putting on seconds-hand, 511, 512. 
" time off telegraph wire, 160, 161. 
" up and letting out spring, 563, 630. 
Tallow for tempering, 66, 70, 78. 
Telegraph, getting time hy, 159 to 161. 
Temperatures, adjustment for, 736 to 789. 
" for annealing, 58, 61. 

" " coloring, 81 to 84, 94. 

" " hardening, 64, 78. 

" " tempering, 66, 68, 69, 70, 71, 72. 

Tempering cylindrical springs, 80 ; spiral, 92, 103. 
" gold springs, 99; palladium, loi. 

" or setting, 151. 

Tempering, springs or steel, see under head of Steel. 
Tendency of modern manufacturing, 2. 

Terminal curves, 589 ; plus, 596 ; minus, 596, 598 ; mixed, 596, 599. 
" " adjusting isochronism by, 602 to 607. 

" " beginning or end of, 596 ; junction, 596. 

" " bending, effect of, 631 to 636. 

" " effect of form, 634 to 636. 

" " form reverts after bending, 625. 

" " forming, 649. 

" " " gauge for, 616; tools for, 249, 250. 

** " functions of, 590, 594. 

" " manner of attachment, 621, 622, 

" " " effect of changing, 622, 624, 634 to 636. 

" " Phillips', 542, 548, 549, 594, 597. 

" " " center of gravity of, 543 to 546. 

" " proper form of, 548, 589, 595, 609, 617, 619. 

" length of, 619. 
" " regulator on, 582, 583. 

" " rigidity of, 591. 

" " tweezers and pliers for forming, 249, 250. 

" " with concentric arcs, 579 to 582. 

Terminal curve, the, mathematical theory of, by Phillips, 541 to 549. 

" mechanical " " '* " Excelsior, "5S9 to 607. 

" " " spiral, "Excelsior's " theory of, 629 to 636, 654. 

"Excelsior's" theory of form of, 634 to 636. 
Testing balance, size and weight of, 141, 142. 
" " of cylinder watch, 421, 423. 

dial, 340. 
" for magnetism, 37; tester for, 37. 
" in long and short arcs, 386. 
" " positions, manner of, 706, 709, 711, 
" " " stock w^atches, 731. 



INDEX, 363 

Testing the isochronism, 522, 523, 676. 

" " only true test, 525. 

" "quick test," 524. 

*• " poise, 302. 

'* polarity of magnetized objects, 40. 
Testing hair springs, 210 to 220. 

" " " by hair-spring gauge, 211, 212. 

quick test, 223. 
" " " " opposition of vibrations, 221. 

" " " " reversal or coincidence, 222. 

■" " " " vibrating the balance, 213. 

" "weighing," 210. 
•• " " for freedom of pinning and position, 285. 

** " " for poise, 295, 296, 297, 302. 

Theoretical isochronism, 536, 547, 554, 555, 560. 
Theoretically isochronous springs, 660, 664, 665, 668. 
Thermometer for tempering, 72. 

Theory of flat spiral springs, "Excelsior's," 629 to 636, 654. 
" " form of springs, "Excelsior's," 634 to 636, 654. 
" " terminal curves, see under head of Termmal Curves. 
Tight, dial should be, 21, 338. 
Time, setting to, 307 ; also, see under head of Settmg. 

" standard, getting by observation, 162; by telegraph, 159. 
" " with box chronometer, 170. 

** " " mirrors, 172 to 174. 

" " " regulator, 157 to 169. 

** " " secondary clock, 171. 

** " " vibration marker, 175. 

" taking off telegraph wire, 160, 161. 
Times, comparing, 334. 

" recording, by chronographs, 161, 176 to 181. 
" registering and comparing, 176 to 181. 
Timing-balance, 218 to 220; bells, 209. 
Timing in reverse, 721. 

" or quarter-screws, 346 to 348, 764. 
" prerequisites of, 15, 314, 315. 
" watch in "Excelsior's" tool, 243. 

" " " positions, 422, 448, 698 to 735, 709. 7ii. 732, 733 ; also, 

see under head of Positions. 
Tools, demagnetizing, 52. 

" for fitting hair springs, 224 to 247. 
" " putting on seconds-hand, 512. 
" " winding hair springs, 89 to 91, 103. 
Top of balance, 702. 
Treatment of steel, 54 to 72. 
Trials for faults of poise, 713. 
'* " position faults, 711. 
" observatory, 387, 388. 
" of isochronism, best arcs for, 710. 
True explanation of isochronism, 556 to 558, 601. 
True purpose of isochronal adjustment, 681. 
Turns of spring, complete, 564 to 566; fractional, 567. 
Tweezers, automatic, for holding spring, 246. 

" curve forming, 249, 612 ; uses of, 612 to 615. 

" elbow bending, 250; heating, 613 to 615. 



364 INDEX. 

U. 

Under-Compensation, 749. 

V. 

Various temperatures for tempering, 69 to 71. 

Varying watches, 321, 322, 324. 

Vibrating tool for springs, 247. 

Vibration, dumb-, of chronometer, 485; impulse-, 485. 

Vibration-marker, 175; registers, 194, 195. 

Vibrations, calculating proper number of, 128 to 138, 182 to 192, 264. 

" comparing, by opposition, 221, 366. 

" " " reversal or coincidence, 222. 

" " with timing-balance, 218 to 223. 

" " " watch, 214 to 217. 

" counting, 193 to 209, 271, 272, 310, 311. 

" " till reversal or coincidence of, 205. 

" extent of, best for trials, 710. 

" " " detecting position faults by, 704, 705. 

" " " measuring, 703 ; varying, 518, 519, 662, 671 to 673. 

" finding desired number of, 264 ; by gauge, 266. 

" large and small, 662. 

" observing the, 694 (20). 

" proper number, for chronometers, 477 ; for cylinders, 397. 

" " " " duplex, 428 ; for levers, 454. 

" registering the, 196. 

" short, to quicken, 593 ; to retard, 593. 

" testing springs by the, 213. 

Vise for holding Breguet springs, 253, 650. 

W. 

Waldo's method of demagnetization, 43. 

Watch, taking time off telegraph wire by a, 160, 161. 

" timing in "Excelsior's" tool, 243. 
Watches, comparing with regulator, 365 to 375. 

" " " " with assistant, 375, 376. 

" compensated, ordinary rates of, 788. 

" fine, regulating, 336 to 360. 

" magnetized, 30, 31, 41, 695 (6). 

" regulating, 312 to 335. 

" setting to time, see under head of Setting. 

" varying, 321, 322, 334. 

" winding and regulating, 317. 

Ways, quick, of bringing a spring to time, 305 to 311. 
Weakening spring by acid, 330. 

Weight and size of balance, 12, 125, 126, 139, 449, 694, 697. 
" " " " " for cylinders, 318, 319, 423, 456. 

" " " testing, 141, 142. 

What is compensated for, 739. 
What isochronism depends on, 535 to 551. 
What rating is, 361. 

" the isochronal adjustment can do, 660. 

cannot do, 661, 662. 
Winding springs, 91, 103; tool for, 89, 90. 

" the regulator, 168. 
Workman, to become a good, 3, 9. 



THE ART OF ENGRAVING 



TH£ ART; 

■ : OF'-; • ■ 

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A Complete Treatise on the Engra- 
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;Bound in silk cloth ; 198 pages and 316 illustrations. 

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THE KEYSTONE PORTFOLIO 
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THE OPTICIAN'S MANUAL 

VOL. I. 

By C. H. Brown. M. D. 

Graduate University of Pennsylvania ; Professor of Optics and Refraction ; formerly 

Physician in Philadelphia Hospital ; Member of Philadelphia County, 

Pennsylvania State and American Medical Societies, 




Chapter I.- 

Chapter II.- 

Chapter III. 

Chapter IV.- 

Chapter V.- 

Chapter VI. 

Chapter VII.- 
Chapter VIII.- 

Chapter IX.- 

Chapter X.- 



The Optician's Manual, Vol. I., has 
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edge, as the titles of its ten chapters show : 



-Introductory Remarks. 

-The Eye Anatomically. 

-The Eye Optically ; or, The Physiology of Vision. 

-Optics. 

-Lenses. 

-Numbering of Lenses. 

-The Use and Value of Glasses. 

-Outfit Required. 

-Method of Examination. 

-Presbyopia. 



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Bound in Cloth— 422 pages— colored plates and illustrations. 

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THE OPTICIAN'S MANUAL 

VOL. II. 

By C. H. Brown, M. D. 

Graduate Universitj^ of Pennsylvania ; Professor of Optics and Refraction ; formerly 

Physician in Philadelphia Hospital ; Member of Philadelphia County, 

Pennsylvania State and American Medical Societies. 






The Optician's Manual, Vol. II., is 
a direct continuation of The Optician's 
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It covers in minutest detail the foui 
great subdivisions of practical eye refrac- 
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Myopia. 
Hypermetropia. 
Astigmatism. 
Muscular Anomalies. 



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This book fills the last great want in higher refractive 
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of professionalism. 

Bound in Cloth— 408 pages— with illustrations. 
Sent postpaid on receipt of $1.50 (6s. 3d.) 



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SKIASCOPY 

AND THE USE OF THE RETINOSCOPE 



mmF^ 



.^LusT^vrro 



A Treatise on the Shadow Test in 
its Practical Application to the 
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It not only explains the test, but expounds fully and explicitly 
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Sent postpaid to any part of the world on receipt of $i.OO (4s. 2d.) 



Published by The Keystone, 

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OCT IV 



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